You can. All you have to do is find a"rom" for whichever one you want then get an "emulator" for the system it's for. Project64 is the best Nintendo 64 emulator.
No. The 3DS does not have a slot for GBA Cartridges and therefore cannot play GBA games.
To play Pokemon games on computer you have to download a emulator I would recommend these: Desmume No$gba (not for gba games) and for playing gba games: Visual Boy Advance
no.
No although it's impossible to use the GBA for the game. You can use the GBA to play the pokemon games that are compatible with Pokemon Stadium
No$gba emulator can play Pokemon games and all kinds you name it!
The Gameboy Color does not play GBA games. Pokemon Crystal Version would work, but Leaf Green would not.
gba beacause it has abunch of mario,pokemon,and zelda games + you can play gbc and gb games on a gba console. ps i recomend gba sp :)
download a Pokemon gba ROM and no$gba
No, You can only play mulitplayer against games of the same generation. So as Ruby is a GBA game, you can not play against the DS releases (Pearl, Sapphire and Diamond). ALthough, if you own a ds or ds lite you can use the gba slot in import the Pokemon from your gba Pokemon games into the ds games.
No, you cannot migrate GBA Pokemon to Pokemon Black/White.
there are way different types so if you want to play gameboy color games you must get a gbc, gb or gba if you have the dsi then you cant play gba games either
You can't. You can transfer Pokemon from your GBA games to Heart Gold, however.