I realize this topic is kinda old, but if your discs are scratched I recommend a disc doctor.. You can buy them at most electronics stores.. Best Buy, Circuit City, hell.. we even had them at Suncoast.. They are like $30 but they are miracle workers and have saved me more times than I'd like to remember..
Excellent for buffing out an unreadable disc.. They won't fix deep gouges, but scratches and stuff like that they are seriously the best..
And when you make a copy of a disc it has to be readable .. That's why its a pain to copy rented games from a video store.. Usually they are so scratched you can't do it..
Anyway.. Get a Disc Doctor.. you can probably order them via the net .. Just google Disc Doctor..