Atari 2600

The first Tomb Raider.

Purchased in this order: Dreamcast, PS2, Gamecube and then Xbox.

Street Fighter II: Special Champion Edition (Genesis)

If you're like me and prefer to have the version with the best music in it, check out: Earthworm Jim 1 for Sega CD and Earthworm Jim 2 for Sega Saturn.

Sonic and Thunder Force games.

To me, if you haven't guessed it already it was Mega Man. Playing through this stage its what really made me like and appreciate games even more.

Yes and no. Clearly the Sega Genesis and the SNES are some of the best consoles if not the best, to me at least it is my favorite combo. However, I would put nostalgia over anything, that's just how I feel, so for me it has to be the NES as my system of choice. Though, the Genesis and the SNES aren't too far from behind.

I really can't choose between...

Chrono Trigger: Favorite RPG on SNES. If not the best, just slightly behind Xenogears.
Super Metroid: Same as everyone had already stated before me..
Donkey Kong Country 2: My absolute favorite platformer game of all time.

Really any 8bit theme would do for me: Journey to Silius, Phantasy Star, Double Dragon, compilation of sms themes awesome stuff.