If it is a store-bought CD, it's probably a bit more rugged than CDRs (the kind you buy) And the CDRs you buy are different in quality, too. I bought some real cheap store brand from CompUSA and it turned out the recording layer was painted on the top of the plastic, so if you wrote on the top or scratched it, you lost your music.

Anyhow, store bought CDs can be fixed with those inexpensive kits. I had a bad scratch I was basically able to recover from on a Screamin' JAy Hawkins CD I didn't want to lose. One important point: If the scratch is circumferential, you have a lower chance of recovery, for there is a lot of data in sequence that is potentially compromised, if the scratch is radial, you have a real good chance of fixing it, and of course, the less deep the better in both cases.