While searching for something to polish up my brass paintball gun, I stumbled across the perfect compund to repair CD's.
Step 1: What you need!
1 CD that is in desperate need of repair
1 roll of paper towel, and not necessarily the soft stuff
1 roll of reasonable soft and durable toilet paper
1 cloth do place the CD on as to not damage it, and soak up excess Brasso
1 Can of Brasso Metal Polish (MUST BE BRASSO)
Take a look at the intro picture to see what I used.
Brasso is a very unique polishing agent. It is just abrasive enough to remove mild to moderate scratches without being so abrasive that it will scuff the polycarbonate plastic..
One of it's listed uses on the back of the can is for polishing plastic watch crystals.