A Mario game doesn't need a story, but games like Zelda, FF, MGS, Ninja Gaiden, and even platformers like Megaman need story, especially the way the classic, X, Zero, ZX and Legends are linked with each other...

That's kind of the problem.  Boys in my age group that I know seem to refuse to read during leisure time and they like to watch movies like Transformers.  Girls aren't better off because while they do read, it is mostly stuff like Twilight.  Teens don't seem to want a good story.

A story doesn't need to be laid out like in a book nor to be plot-heavy to add value and -dare I say it?- depth to a videogame. So to say that games have "not good enough" stories when comapred to books and movies sounds like trying to hammer a square peg in a round hole.

One of my favourite games of all time - Shadow of the Colossus - has a quite understated narrative. I found that it made for a wonderful experience, whereas other players didn't even get most of it. It surely isn't much if you try to summarize it into a plot, and it doesn't try to be literature nor cinema. Still, it's great storytelling.

It does FEEL like it is a great story and does have a number of good individual elements.  I personally consider MSG4 one of the best SIMULATIONS of a blockbuster movie ever made. 

A purpose doesn't necessarily have to be a story.  It could be something simple as a goal.  This goal can be to change a game environment to match a certain objective, or defeat an opponent using the environment.  What also gets lumped into games are sandbox games.  These include games in the sim series, where you are a god over the environment, or one where you just jump around and explore and shoot stuff, like in Crackdown (or the original 2D GTA).  And games that rely on what I just wrote don't necessarily have a story.

It's a matter of taste and the type of game.

Tower defense games are amazing games, and most don't follow a story.

Games don't need stories... but I like games with good stories.

Good question... I'm going to ask to mister Victor Hugo or to Shakespeare, maybe they'll have a clue. If not, Orson Wells or Stanley Kubrick might have an idea

Jeeze...

Just to clarify, a decent story (relative to video game stories in general) doesn't take away from a game, but it doesn't add to it from me.  I haven't played SotC (no PS2), but good story telling seems to conflict with good gameplay, generally.  As is already mentioned, video games are about giving you control over the situation and overcoming some challenge.  Enjoyment comes from beating it through your own skill.  However, by giving you power, developers are giving up power of their own (in terms of controlling what happens and, in turn telling a story), and this limits what they can do in terms of story telling.  It's not impossible, but it certainly makes good story telling more difficult.

Back in the day most of a games backstory was relegated to the back of the box and the instruction manual. You played the game to reveal the rest of the story. To many games today make you watch the the main plot points instead of playing them.

Don't get me wrong, I enjoy a good story and glad to see games evolve, but I wish more games could use Bioshocks story mechanic. It keeps you in the game amd immerses you even farther into the world.

I guess what it comes down to is that I buy games to play, not watch. There's to many movies out there with much better acting and plots for me to sit down watch a game.