DAMN! This Question is a hard one ^^"
there are many different types of games and each of it has its own strengths which make me happy when i paly them
Therefore I have several favorites which can't compete due to their different genres.
RPG --> Persona 3/4 , Final Fantasy IX, Diablo 2
Jump'N'Run ----> Super meat boy, Super mario World, Metroid, Metroid Fusion, Metroid Zero Mission
Racing: NfS MW, Forza, Mario Kart Wii
Strategy/Tactic --> Warcraft3, Fire Emblem, LoL, Dungeon Defenders, all the pokemon Games
Action ---> Dead Space, Dead Space 2, MGS 3 Subsistance, Zone of the Enders
Beat'em up ---> Soul Calibur 3, BlazBlue calamity Trigger