[CentOS] C5 i386 DVD boot problems

I tried to boot from two different CentOS 5 DVDs, both pass the checksum test, and both give me the same error on a Dell laptop from either GUI or text install modes:

invalid compressed format (err=2) VFS: Cannot open root device "<NULL>" or unknown-block(253,0) Please append a correct "root=" boot option Kernel panic...

I did some google searching and learned other people have had the same problem, but no resolutions were ever posted.

I'm downloading the CD version and will see if that makes any difference.

Assuming it won't make a difference, how do I resolve this so I can get CentOS installed on the system?

Thanks.

Scott