I have played it actually, yeah it's quite fun!

#29 New Pokémon Snap

Taking pictures and gathering points. That's it. And it is glorious. I bought the original thinking that I could walk around freely in a sort of safari-zone looking for Pokémon that roomed around. Was disappointed that it instead was played on rails. But I already bought it, might as well play it. What I found was I game I did not except as much as I did. Seeing the Pokémon alive like never before in a game was still awesome and soon I found myself playing and replaying the same levels over and over just to snatch a few extra points.

Adding the newer game here instead of the original since they are very much alike but the later version is a much better game with a lot more content, more pokémon, more courses, more poses, more environments... but less flute tracks. My go to cozy game for the past years.

#28 The Legend Of Zelda Links Awakening

My cousin owned a game boy. Sometimes we could borrow it. He had 3 games, Mario Land 2, Tetris and Zelda Links Awakening. All fantastic games but Zelda was something special. It was the second game I ever played of the franchise and for many years I did not think that highly of it. But with each revisit I started to see the game for what it was, a little miracle on the game boy.

Playing this game is the first time I remember a story in a game making my mind go wild. The eerie music when I gathered the key to the sixth dungeon and for the first time got to know the truth about the island and the faith that awaits. The memory still gives me goosebumps and it is up there with the first Planet of the Apes movie in mindfuck impact. And the Eagles tower, man what a great Zelda dungeon. 

#27 Kingdom Hearts

The next generation had already started when I bought my PS2. There was a lot of people selling off their collections in order to buy the next big thing. I bought two full paper bags with games for about 100$, I think it was around 60 different games. Then spending a few days trying game after game sorting them into piles of junk and funk. Kingdom Hearts made me stop halfway through the pile since I was mor interested in finishing that than try to sort out all the games I would trade in at retail. 

Different Disney worlds. Leveling up but with real time combat. Explorations and a stupid but engaging story. I loved it. I even loved modifying my gummy ship. Seeing a beloved character from my childhood and hearing tracks of familiar music gave me such joy. And when I got the ability to glide across the air and could explore the rooftops it was like the best lucid dream. Never thought the second game was as good and did not continue the franchise after that one. But man playing this game back then made me so happy.

#26 Ico

This was a surprise. Picking it up from the paper bag I did not think much of it at first by looking at the game case. But man I'm glad I gave it a serious go. The gameplay felt almost empty. Most games have a lot of bars, collectables, timers, weapons or other stuff in a hub around the screen. Ico was in comparison empty, playing on the isolation it conveyed. I know that it is a sort of cliché but playing Ico was the first time I truly recognized video games as art.

Without the ability to communicate grabbing our sole companions hand and dragging them along the castle. It just struck me as so heartfelt and true to the world it displayed. Holding her hand was like the game holding my heart and each time I needed to let go and leave her my heart stopped for a minute. There have been games that could match the game as an art formula, but no other game have struck such pure raw emotion as Ico did.   

#25 Secret om Mana

Sparkling with colors and charm. Brining a unique battle system where action packed sword combat goes hand in hand with a timer based magic system. I really liked that action elements could join classic rpg concepts like leveling up. Playing two players at the same time co-op in a game like this was marvelous. I have played through the game three times with different people by my side. Getting stuck in different parts of the game each time. I kind of like getting stuck and revisiting each place four times before stumbling over the solution.

This was the first time I got introduced with the concept of finally getting a means to move around the world freely visiting each mysterious part of the world. For the longest time I thought the last boss was my flying companion Flammie that had been corrupted or something by a dark power making him the mana beast. When I replayed the game with the ability to read and understand English and got to know that was not the case, I actually felt like the game was worse for it. 

#24 The Legend of Zelda Skyward Sword

Some of the best dungeons in a Zelda game. When this arrived on Wii it placed itself at the top of my favorite games list. I need to replay this game in order to see how it holds up, but to this day playing through Skyward Sword is the best first run of a game I have ever experienced. I like linearity with some freedom, I like characters with some development and I like motion controls. I even liked the circle menu to select items, reminding me of another game just below this one on the list.

This game gets a lot of dislike for many things and i must say that what I read about it might have affected my ranking of it negatively.  But I had no problem with revisiting the same areas. I thought recalibrating the control was awesome since it made it easy for me to change my hands position. As stated I liked the linearity. I can see how the imprisoned was bit annoying to replay, but man did I like this game when I played it. I'm afraid to replay this game and finding out that, no it was not the fantastic master piece you remember, but until then I will keep imagine that yes it was.

Well, since nobody tried all those days I will reveal the first one and add a bunch more games and hints to the list:

#40 - A Pinball game with 3 tables that would be pretty much impossible to make in reality 3D Ultra Pinball: Creep Night

1. It has a halloween/dark fantasy setting
2. "FEED ME!" says the castle
3. The names of the three tables are "Castle", "Dungeon", and "Laboratory".

#39 - Stealth, Sniping or big guns, whatever approach floats your boat in this game is possible.

1. When it came out, the game was absolutely lauded for it's story and storytelling, and it's only real gripe among reviewers was that the graphics were a bit outdated.
2. It's a bit of a meme that people hearing about this game again makes them immediately re-install it on their PC.
3. The game got released just 2 days before Diablo 2 and 3 weeks before entry #37 - at least in the US. In Europe #37 released the same day as Diablo 2

#38 - Thwart an Alien Invasion with a team of soldiers and some researchers trying to reverse-engineer the alien tech into something useable by humans.

1. You start in the late 1970's and with according tech and weaponry, just somewhat adapted for your specific needs. Later on, you'll research laser weaponry, plasma rifles and coilguns, but psionics won't do anything.
2. Your alien foes are made of Sebillians (a race of fasr-healing and very strong but short-sighted lizardmen), Caesan (basically the Greys, good sight but mediocre health), Reapers (turns your soldier into a zombie if he hits you in melee), Androns (robotic infantrymen with a total disregard for cover), Drones, and the Praetor who are leading the invasion. 
3. It got rereleased a year after it's release as the "Community Edition" with some community-suggested rebalancing and mod support.

#37 - "It is a world, of darkness"

1. The quest of this RPG plays over a timeframe of about thousand years, which is foreshadowed in a discussion early within the game.
2. As the thousand years alluded above suggest, you're playing a Vampire, but he's not yet one of them at the beginning of the game.

#36 - This series is one of the most-cited successors to the classic DOS game Master of Magic.

1. The first game of the series was totally broken and got 6 patches within the first two days, but the core mechanics were not really good, so it got a successor that entirely replaced the first game, which itself got an expansion that replaced the previous replacement. We're talking about the last one in the line.
2. You play as the sovereign of one of the 10 nations, split between the good Kingdom faction and the fallen Empire faction

#35 - You lead the development of new video games for a console manufacturer

1. The game only came out in Japan as it released just days before the console stopped being produced

#34 - Careful what you build here, because those living in your facilities might get violent, kill each other or even their hosts, riot, or leave the complex you're building for them entirely.

1. While the player character is represented by a unit in the game, it's name, gender an special skill are set. and you can't do research on your own, you need some Administrators with their office unlock these things. Prison Architect, as found out by @S.Peelman 

#33 - One of the most hailed tactical RPGs on PC - if not THE most one.

#32 - A medieval Fantasy city/city state builder.

#31 - Two drivers on the same vehicle Mario Kart: Double Dash, found out bby @Darashiva 

#30 - "Capitalism, Ho!" Recettar: An Item Shop's Tale, found out by @Darashiva 

#29 - "War never changes", again. Fallout 2, as found out by @UnderwaterFunktown 

#28 - "Game Over, Yeah!"

#27 - Heroes lead armies in turn-based combats over a large world map to dominate their opponents and conquer their cities.

#26 - The goal of this game is to colonize Mars and make it habitable to humans without protective gear or oxygen masks.

#23 Mike Tyson's Punch-Out!!

The second best game on the NES. Full of stereotypes to punch and a daunting last fight against a real world heavy weight champion. Probably the first game I can remember with licensing of a real person. Simple and effective gameplay with pattern recognition as the main strategic tool to archive a knock out.  

I still play this game now and again. It holds up so fantastically well. And the last fight against the titular champ is as difficult as ever. It took me years before I beat him for the first time and it actually felt like I took down a true master at his craft. 

Don't think I know many of these but might as well try

38) is this an X-Com game?

33) is this an X-Com game?

29) Fallout 2 I guess

27) Heroes of Might and Magic... 3?