If that happens with different computers, 99% of chances are that you have a bad CD/broken iso. Maybe you could download Redhat again and check the .md5 to make sure it's a perfect iso.
Unconnected but... sometimes... I've burned a distro in a CD-r and it did not work... I then burned into a CDrw and it worked... go figure
Good luck and welcome to LinuxQuestions.org!