I doubt that there is any problem with the DVD.
The following file should contain a list of the files required by setup.exe together with their target directories.
The following commands, when executed from within a CMD window, will list all the files on the installation DVD and save this list to the corresponding file (X: is the drive letter of the DVD).
dir X:\ /s /b > dvdfil_b.lst
dir X:\ /s > dvdfils.lst
The following command should read each file on the DVD and copy it to the NUL device. This should test the integrity of the DVD.
echo f| xcopy X:\*.* nul /f /c /e /h > \temp\xcopy.log
It shouldn't be too difficult to write a batch routine to confirm whether each file called for by LAYOUT.INF exists on the DVD.
If any files are compressed and need to be expanded, it should be possible to test them via another batch routine.