[CentOS] CentOS 6 x86_64 DVD doesn't boot

>> By any chance is the drive that does not work *NOT* a CDRW drive?
>> Sometimes CD-ROM drives do not like reading rewriteable media.
>
> The drive in my little server is a DVD/CD burner, too.  So, that's not
> the problem.

Can you read other discs burned by that burner in the server machine?  I 
understand that it has a DVD/CD burner, but is a CDRW burner?  Can you 
attach this drive to a USB cable or move it to the affected machine to see 
if the problem follows the drive or the machine?