I have many favorites and hates:
Favs
Nintendo:
NES-Zelda rules and you can't beat the classics
SNES- Starfox, Super Metroid, many more jewels
N64- Oot, Majora's Mask and Goldeneye, ergonomic controller
GCN- Twilight Princess, Starfox Assault, cute cube
Sega:
Genesis (and CD/32x): Sonic CD, Shadow Squadron, Sonic 1-3.
Saturn: VF2, NiGHTS, Sonic R, Panzer Dragoon
Dreamcast: Easy to pirate, dual blade controller, VMU, Sonic AdV 1&2, Virtual On:OT, many more
Hated:
Sony PS series: All cruddy poor construction, over priced
Nomad: Poor battery life, bad caps
Atari 7200: Weaker than 5800, bad gfx