Is it a copy? If so, that could be your problem. If it's not a copy, then I apologise, but it had to be asked. Are there any scratches on the CD? Is it dirty? Try giving it a wash in some luke warm water with a tiny bit of detergent. Dry it carefully and try it again. You might need to do that a few times. Seriously it does work with some problem CDs.
Tope's right about the copy , if a copy is authored on the wrong software or with the wrong settings it will be all ok except for it won't boot ...
scratched disk is also possible , actually i use a ligt spray of furniture polish to rejuvinate a CD , make sure you use a clean soft cloth and wipe from the centre going outwards , it's fixed many a disc for me
Ep, glad to see you come back and tidy up...did want to ask a one day favor, I want to enhance my resume , was hoping you could make me administrator for a day, if so, take me right off since I won't be here to do anything, and don't know the slightest about the board, but it would be nice putting "served administrator osnn", if can do, THANKS