I don't think the roms matter. I think it the emulator that is different. I havn't tested it yet. Maybe someone else knows.
do you mean can you get roms for a certain emulator, ie genesis, neo geo etc, and use it on your genesis , neo geo emulator? or do you mean just use roms on ANY emulator. Im a bit confused as to what youre asking. As long as you get the RIGHT roms for the correct "system" that the emulator is emulating, you should be fine.
you got my question right. I just thought it had to be a certain rom for the xbox but it seems not. and yes i know that you have to have n64 roms with the n64 emulator etc, etc.