Joe,
Make sure you have all of the critical updates for XP. Disable your virus software and quit out of any running programs. Then try it again. If that still fails there are a couple of options that remain. 1) Install in Safe Mode, 2)Copy the contents of the CD to your desktop and install from there. 3) I’ve also heard of the occasional case where it hangs like this, but does complete after a while. You can try going to bed and see if it completes overnight.
Rich