[marsan]

That error message means that the installation program can't read from a part of the DVD(or to be accurate, it can read it, but what it reads doesn't match what it expected to read, which usually is a result of a damage disc or production error). Either the DVD disc is defect or there is an issues with your DVD ROM. If you have tried the DVD disc on more than one DVD drive the DVD is probably defect, and it's probably an production error unless you notice scratches on the DVD. My (unofficial) advice is to return the DVD to the store and either ask them to test it on a computer they got there(to confirm the issue) or to give you a replacement disc. At least, that's what I would have done.