Fun thread idea!

I'l break this down into time periods.

Overall:

3) Capcom - yes, the studio has a spotty recent history but it delivered amazing games in several different genres: Street Fighter, Devil May Cry, Resident Evil, Zack & Wiki, etc. Resident Evil 4 still sits in my top five list.

2) Rare - its quality diminished greatly after 2000 but before then it turned out what seemed like one great game a year, sometimes several great games a year. Quality titles include Jetpac (when it was known as Ultimate Play the Game), Donkey Kong Country, GoldenEye 007, Banjo-Kazooie, and Perfect Dark.

1) Nintendo - the hardware maker started making great games in 1982 and never stopped. 17 of my top 50 games are developed by Nintendo

Last ten years, 2008-2017:

3) From Software - Demon's Souls was a revelation for me, and Dark Souls captured my imagination

2) Monolith Soft - I don't even want to imagine a world in which Xenoblade Chronicles never arrived in North America

1) Nintendo - the past decade, like all decades, has been productive for Nintendo, which turned out great games in Wii Sports Resort, Skyward Sword, Super Mario Galaxy 2, Mario Kart 8, A Link Between Worlds, Splatoon, etc.

This year, 2017:

3) Capcom - Resident Evil 7 turned out to be the best game in the series since the sixth gen

tie-2) Inti Creates & Lizardcube - both tiny studios punched well above their weight with a pair of awesome retro remakes. Inti Creates turned in Blaster Master Zero and Lizardcube resurrected Wonder Boy: The Dragon's Trap

1) Nintendo - it would be hard to snub Nintendo when it released arguably the greatest game ever made in Breath of the Wild, and a racing game for the ages in Mario Kart 8 Deluxe

As far as all-time favourite is concerned Square Enix/Squaresoft takes it pretty much by default. They've made and published a huge number of my favourite games over the years, so it's not really even a contest. Nintendo, Sony and Capcom are also up there on that regard. If we're talking just developers then From Software, Atlus and Falcom are very high up these days

8-Bit - Nintendo, Enix, Konami
Gameboy - Squaresoft
16-bit - Squaresoft, Rare, Sega
32/64-bit - Nintendo, Rare, Square
PS2 generation - Rockstar, Namco/Monolithsoft.
GBA - Square
Wii generation - Nintendo, Rising Star/Marvelous,
Wii U/3DS generation - Nintendo
Current generation - Nintendo

No Blizzard in poll? I'd go with Nintendo over Blizzard but Blizzard deserved at least a spot on the poll. They might have fallen in my book but they still chug along.  I know Activision owns Blizzard now but even in their name they keep them seperate. 

Bioware: Mass Effect, dragon age, jade empire, kotor, nuff said😜

As of recent, Atlus, Blizzard, and Nintendo.

Publishers:

1. Sony
2. Nintndo
3. Take Two

Developers

1. Naughty Dog
2. Guerrilla Games
3. Polyphony Digital
4. Rockstar North
5. Kojima Productions

Sony is easily my favorite Punlisher for their unending dedication to bringing new experiences, and willingness to take chances on games even if their is not a huge apparent audience. In my opinion they do the best job balancing their IP, not over saturating stuff when it succeed, and willingness to give even successful stuff a break to try new things.

Nintendo I appreciate for their ability to create lasting IP, that can truly span all generations. They have made some of my favorite games of all time, and they have a great talent for delivering games that remain enjoyable regardless of the generation or times.

Take Two is easily my favorite 3rd party. They deliver so many games that come from do many different places that they really have something for everyone. To me Take Teo is basically a 3rd party version of Sony. Always willing to try new things, and push the medium to the next level.



Naughty Dog has been my favorite studio since Jak and Daxter. As they progressed to Uncharted they began to extend that lead. Then they went and made what in my book is head and shoulders the best game ever made in The Last of Us. This team is amazing, and I hope they can continue to deliver.

Guerrilla Games has been doing an amazing job with the Killzone franchise for years. The Killzone franchise has been my favorite FPS for a decade, and after playing Killzone 3 in 3D with PlayStation Move, I havr not been able to enjoy any other FPS since on the same level. Noe they went and put them selves side by side with Naughty Dog after the release of Horizon, absolute masterpiece.

Polyphony Digital totally changed my perception of games with the original Gran Turismo. Until then games had always been a cartoon or fantasy setting. When I saw Gran Tutismo the first time it was like a whole new world opened up in my mind. I can not wait for GTS.

Rockstar North, GTA, does anything else need to be said? The ultimate in what can be done with mass amounts of time, money, and man power. It may be as casual as casual gets, but it really is great fun every time, and keepz me coming back for years on each release.

Kojima Productions, Kojima. Metal Gear Solid was a staple of my childhood. I missed MGS on the PS1, and started the series with MGS2. This was the first game I ever sat down and played start to finish, which lasted well over a full day. In my opinion the series got better with each release through MGS4. Some of my kost memorable gaming moments ever Though I really didn't like the latest game, I am still on edge over what is coming with Death Stranding.

In all honesty, there are dozens of development teams I love, and I could go on for days. Games are my life, and have the upmost respect for everyone in the industry. My favorite thing is new experiences, and opening doors to allow people to experience either real life things they could never afford, or fantasy things that can change peoples views on games or life in general.

Nintendo

Sony as favourite publisher
Naughty Dog as favourite Sony studio

Take 2 and Rockstar coming in second for obvious reasons (GTA and RDR)

3rd I don't own a Nintendo console so I guess publisher Namco Bandai because of Souls and the Witcher. I prefer Souls over the Witcher so From Software.

Never really paid much attention to who developed what up until a few gens ago, so I'll stick with publishers.
3rd Gen: Konami
4th Gen: Sega
5th Gen: Squaresoft / Square Enix (though Sony published a number of their games, I'll give credit to Square.
6th Gen: Take2
7th & 8th Gen: Sony

Capcom & Nintendo ranked high 3rd-5th gen, but didn't make my 'favorite list.'