If your looking for a SNES emulator, try searching SNEmulDS and see what you get because I have it and it is v.good!
Already suggested. And no, NDS cannot emulate N64. There are some ports with extra features, though, like: Super Mario 64 DS Diddy Kong Racing DS
It should, yes. Some games won't work due to an extra chip in the original game because the SNES wasn't powerful enough to play the games by itself. I forget what it's called, but Apo knows.
You first need to put the ROMs into a SNES folder onto the root of your SD card. Then run the emulator's NDS file. Then you must select the ROM to play, and play it.
the extra chip in super mario kart is copy protection. the chip that ace101 is talking about is the superfx chip used in starfox and pilotwings among a few other games.
...copy protection? lol Did nintendo already knew that technology back then..? It plays fine on my Wii, though, it just won't work on the DS.