Never be afraid to try new thing with your computer
That is unles it is dealing with information you don't have backed up and need!
go to
http://www.linuxiso.org./distro.php?distro=7 download the *.iso files for the 3 install disks under redhat 7.3 Don't worry about the SRPM images.
Open you favorite CD burning program and find the option to burn a cd image (or equivlant wording) and select the first iso file. Burn away.
Once the first one is done, you can test that it works by booting you new system with that CD in it's drive. You'll usually need to burn the other 2, depends on the options you select when installing. Follow the prompts ect on the screen. Linux usually needs to know some information about the hardware you have installed. It is easiest if you have this information written down just in case. (sysinfo report fom windows will usually suffice)
If the system won't boot of the first CD you made, double check that your bios is set to boot from a CD