Joe Forster/STA posts a very good guide. Because I buy most of my games second hand I tend to get a lot of scratched discs. Because I am a tight git I always see if I can repair things myself. I have used silicone wax floor polish on scratched CD/DVDs and rubbed it in with Jay cloth until there was no excess visible. Then I leave the discs for the night and the next day they play almost flawlessly. No method works 100% for all discs. It really depends on how bad the scratches are
