I've done some research on cd repair.

As we all know, a CD is a sandwich of two pieces of acrylic and a piece of aluminum foil. The acrylic on the "play" side is thicker than the acrylic on the "label" side, so it is generally true that a scratch on TOP of the CD will be more likely to affect repairability. But the real issue is the foil.

Hold it up to the light. If there is a hole in the aluminum foil, there will be a pinprick of light. These canNOT be fixed, so if there is a skip there, you're stuck. (Remember a CD plays from the inside out, so a scratch near the middle will affect earlier tracks, and a scratch near the periphery will affect later tracks.) Not all pinprick holes in the foil will cause skips or drop-outs, though, because the data is recorded somewhat redunantly. Some skips can be filled in by the logic circuits of the CD player from the redundant data.

There is a used CD shop really close to where I work that has a very sophisticated scratch-polishing setup. I myself have a tube of scratch cream of some sort which I use for the little scratches. Larger ones I take to the cd shop. If they can't fix it, I have to buy a new copy.

If this is a one-of-a-kind CD, that you can't just run out and buy a replacement for, then you can always record the tracks as WAV files and use a WAV file fixer-upper program (many exist) to fix the data loss. These programs will generally take some of the sound from either side of a skip to fill in the missing data. Then burn the whole thing onto a new CD-R (or CD-RW).

A word to the wise: NEVER store your CD's in one of those sleeve-insert type albums for long periods of time. And the larger the album (more pages, more CD's per page), the more likely it is to slosh around (say, on a car seat) and rub holes in the CD's. I lost about 10 cd's out of a 244-cd album before I learned this! Tiny bits of dust and rock will get in there with your CD's, and every time the album shifts, the dust and rocks will dig into the CD's. Eventually they get all the way through the acrylic and put holes in the foil. Arrrrgh!

Alex