With the announcement of the mini-SNES release in September with 21 classic games, I was trying to think of my favorite old Nintendo games. Really difficult to come up with 1 for each system, but here goes nothing:
Nintendo:
Contra
Super Nintendo:
Secret of Mana
Nintendo 64:
The Legend of Zelda: The Ocarina of Time
I am an idiot and forgot Gameboy...
Gameboy:
Pokémon Red