When CD's get stratched CD's tend to corrupt data, so all I can say is get a new CD Rom which is cheap and if you want to used old scratched cd's besure to get a cd repairer if you see any.

All I can tell ya is that the starcraft might be and the autorun might not run all the time, and the autorun file might be corrupted because when you pop in a CD the Drive scratches it to get it started and start reading it, thats why I use the CD Protectors and everything works fine :)

Protecting your CD's is cheaper than repairing your PC and spending tons of money. Even if you do get a new PC your CD's will get scratched :P