Underated
Zelda Oracle Of Seasons/Ages
Amen to that, Nintendo and Capcom were on the ball with those two Zelda games.

Underrated:

Tech Romancer (great mech fighting game)
Cyberbots (a great 2d mech fighting game)
Armored Warriors (fun 2d beat-em-up with...mechs.... that appeared in Cyberbots a year later)
Egg Mania (fun puzzle game with many modes)
Super Double Dragon (great SNES beat-em-up)
Fatal Fury Real Bout (best Fatal Fury game yet, forget Garou MOTW ;D)

Overrated:

Uh... too many to count, sadly, xD