No wonder we're friends, we have a lot of these games in common!
Goldeneye was so fun, as was Super Smash Bros. Ocarina of Time (and A Link to the Past) both make me almost tear up with nostalgia when I think about them. Civilization 5 is probably the game I've put the most hours in... ever.
Randomly, though, I think I liked Saints Row 2 better than any GTA I've played. Part of that might have been Michael Dorn though.