I love almost all my games. My favourite I would say is Age of Empires II which I play over and over again. But I should also give special mention to Ape Escape on my PS which was the first game I ever completed
Hmm... I can't really say for sure what my absolute favourite game is. Though, there is one that I've treasured ever since I first played it: Crash Twinsanity. Man, I love that game!