[seiki]

It seems that it is legal to make a rom from a game you already own but you can not do this with a cartridge game as the machine required is illegal. It is illegal to download a ROM. If you make a ROM as a back up copy you are apparently supposed to treat it as the game as well and if you sell the game you must delete the ROM from your pc or disk or whatever.

Also why would it be legal for someone to make a copy of a game as they are all patented and even the oldest nes, atari and so forth still will be for aroun 45 years.