RPG: Mass Effect 3
MMO: WoW
Shooter: I don't really play shooters, but I loved this game called Strife for the PC
Strategy: Command and Conquer Red Alert
action: God of War 3
stealth: Metal Gear Solid 3 - Snake Eater
Racing: Gran Turismo 2
Sports: Pro Evolution Soccer 2006
RPG: So many to choose from....but I will go for Oblivion