I consider myself to be a game connoisseur, in that I play many different genres. However, by sheer number of games currently owned, my favorite genre appears to be strategy/simulation: I own Warcraft III: Reign of Chaos/Frozen Throne, Rome: Total War, Civilization IV, The Sims 2, SimCity 4, and Advance Wars 2, to name a few.
However, my favorite GAMES of all time are mostly platforms/rpgs... Metroid Prime, Zelda: A Link To The Past, Super Mario Brothers 3, etc.