No, you can download it, as long as you have proof of ownership if whatever company comes a 'knockin. You can legally download songs if you own them as well, just like with game roms on the internet. If you own the cartridge, you can download and keep the rom.
You can make backups of your discs you own, yourself. I think though, in England maybe, they just passed a law stating you can only make one backup of your disc, which is retarded, but no one really makes more than one backup unless they had ideas of distributing anyways. Just them putting it down in law seems a bit odd to me, but whatever.