jei!
" Is your disk scratched up *really* bad? Is your CD drive detecting it after you put the disk in? If it is scratched pretty bad you may try seeing if the CD drive is recognizing the disc. If not maybe try ejecting the disk and puting it back in to see if that does the trick. I know my disk is pretty scratched so occasionaly I have to eject it and try again to get it to work. If that fails you could try creating a image of the disk using Alchohol 120 (or your software of choice) and playing off of it. When MicahW was still modding the forum he did confirm that playing off of an image would not be a violation the the eula."