Welcome to LQ, both of you.
Presumably by did not burn the cds as iso
you mean that when you access the cds, you're only presented with 1 remarkably large file? If this is the case, then check the md5sums, copy the files over to your harddisk and burn again (presuming the md5sums are correct).
You can install from a harddisk, but I'm not sure if it will allow you to install from an ISO file on the harddisk, or if it requires you to copy the files over... although without being able to access the files in the iso files it is gonna be difficult.
You could go to the RedHat ftp site
and download the boot images and rawrite software (the boot images are under the images directory, and the rawrite software is under dosutils directory).
Alternatively, you could download something called Iso Buster
and simply copy the files out of the iso... be warned though, this is not a particularly good idea.
Put the boot.img file onto a floppy using the rawrite util and boot from the floppy. You should be given then option of installing from a CD or from the harddisk... you know which to choose!
Hope this helps, and good luck.