For my wife to be interested to play a game with me, the game should not be too hard, control easy to learn and the most important: CUTE and COLORFUL graphic.
What I suggest;
SNES: Pocky & Rocky 1 and 2, Secret of Mana, Legend of Mystical Ninja
NES: Bubble Bobble, Snow Bros
All the Metal Slug
All the Mario Kart
For more recent games with a "retro feeling", go with Rayman Origins, Rayman Legend, Donkey Kong Country Return, New Super Mario Bros.