I think I'd try copying BEFORE any abrasive cleaning of the disk, just in case the abrasion wrecks it - screen wipes etc should be OK.
Optical drives come in many flavours, some will only read disks and some will also write them, so you can get a drive which will, for example, read and write CDs but will only read DVDs. If your drive will write DVD disks it will also read them but it's no good writing a DVD on your computer and expecting it to play on a domestic DVD player - it might, but no guarantee (the instruction manual should state what disks can be played). On the other hand, if you have a domestic DVD RECORDER, then it should cope with RW disks.