U Didn't Provided your Configuration Can't suggest u the games which u can play on Ur PC.
Any way if u are interested to play high End games Then the following is my Fav list of games
First Person Shooters:
COD Black Ops, Cod modern war fare 2, Cod 4 Modern warfare, Medal of honor, Black Hack Down, Crysis, Gears of War, Delta Force Task Force Degar
Racing: NFS Wanted, Underground.
Horror: Dead Space, Dead to rising.
Action: Assassins Creed, Prince of Persia, Max Pain
Stealth: Splinter Cell-1,2, Conviction, Sniper Ghost Warrior
My gaming ExP