If you really wwant to dual boot between Windows XP and RedHat you should follow a few simple steps.
1. install Windows XP (probably already done)
2. boot to the RedHat CD (disc 1)
3. you do not have to use partition magic or and thing else, inside the RedHat installation wizard (anaconda) you can choose to partition you drive with Disk Druid, choose this option and make sure to create at least two partitions 1st is the EXT2/3 for the linux install and the 2nd is the swap partition.
4. oncethis is done finish the installation, MAKE SURE TO CREATE A BOOT FLOPPY!!! if you don't you will be stuck with a RedHat install and not be able to boot to it.
5. Once the install has finished boot to the floppy that you created and you will boot to the RedHat install, now all you have to do is type lilo or grub (depending on which boot loader you installed)
6. reboot the system and you will then get the option to boot to DOS or RedHat (by default the boot loader names any windows install as DOS, you can change this by editing the config file for the boot loader, either /etc/lilo.conf or /etc/grub.conf)
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