Hey! I love N64! My brother and I still play!
A really cool (but old) computer game is Age of Empires; and Age of Kings. You get to build your own empire/kingdom and battle other societies and try to gain control of as many institutions as possible. It's really fun! You can even command your animals (tigers and lions!) to attack enemies! Nintendo DS is awesome, too! You can play Pokemon games on PC, as well. Have fun!
Yeah, been years since I have used one but searching for "NES ROM Emulator" should do the trick. Hopefully you'll find something worth it. Good luck with your old school gaming.