Gears of War 2: Improved on the first one, which was a fantastic game in its own right, and would be listed here if it wasnt surpassed and bettered by its sequel. Fantastic game and still looks amazing now, Horde mode, brilliant. And the story with Dom's wife Maria!? actually made me emotional
Mass Effect: Fantastic game, maybe Mass Effect 2 would be listed here, if i had infact played it. But no I've still only had the pleasure of playing the first
epic game. The looks, the immersion and dialogue. It took everything that made Knight of the old republic fantastic, took it out of a Star Wars universe, Improved every single aspect of it, and released a brand new adventure, which I happily consider one of the best this generation. Also, The only time I've ever wanted to have sex with a blue alien. What can i say!?
Resident Evil 5: Co-op. I can imagine this game would be frustrating if it was played solo or online with someone who wasnt a friend. But I played it through with my girlfriend, and I have to say it's the best Co-op experience I've had this generation. The new resident evils get a bad rep, as they don't follow zombie story, or they're more action orientated. Who cares when they deliver as well as this does. Played co-op with a friend, this is definitely deserving of a place in my top 5.
Metal Gear Solid 4: Well what can I say, Epicness at its finest, The first 3 were fantastic, and 4 did not fail to deliver in the slightest. You always felt like you were part of something bigger while playing, and the climax to the game!? Actually brought tears to my eyes....is that the second time in this top 5? I'm not a girl I promise.

But yes, metal Gear solid 4. Is probably my favourite game, out of these 5 choices. So gets a number 1 slot.
Call of Duty 4 I'd give this game a top spot just for the sniper mission alone, It was handled fantastic, But obviously there's more to Call of duty than just the one mission. I felt close to the characters, The nuke taking down the chopper! The opening scene, where you're in the back the car. Very well executed...Pardon the pun

And then ofcourse the online aspects of COD4, Brilliant fun. And a very good game to sit around drinking and playing with friends.