Get Skyrim my friend. It's the perfect game! Or wait for Mass Effect 3 next month? Borderlands?! Battlefield 3? These are only some of the games that come to mind. I have them all, and they're all pretty amazing. Well, except for Mass Effect 3 of course! :)
PES 2012.. play with a friend. have fun~!
Counter-Strike Source! more skills, lots of mods, win money, chat with other people etc
Orcs must die! Tower defense, action and good humor. you'll not regret
MINECRAFT obviosly. the best game ever
Garry's mod. ￡6.00 Awesome.
Look it up
Starcraft 2 if your into RTS , very good game large fan base ect ect. You could always wait for planetside 2 (MMOFPS) the battles dont stop you constiantly fight over continents, thousands of players at once.
The Witcher and the Witcher 2: Assassin of Kings. Pretty much the top rated RPG pc game of all time. It has great graphics, a good story, and even several different possible story arcs. Basically the most BA game ever.