The System Setup (BIOS) has nothing to do with Windows XP. Each system has
its own key or keys to press when you power on, to enter the System Setup.
Usually the first screen that comes up when you power on says something like
"Press F10 to enter System Setup." The key to press can vary from system to
system, like F1, F8, or DELETE. If for some reason you can't find that info
on your first screen BEFORE the Windows logo comes up, and you don't have a
manual for the system, which would tell you how to get into System Setup, go
to the web site of the maker of the system and see if you can find the info
there. Or, go to Google, do a search entering the PC makers name, the model
and Enter System Setup as key words for the search. Once in the System
Setup, you'll be able to find a listing for the Boot Order of the drives,
and you'll be able to change the order, making the CD drive the first in the
boot order. then Exit Saving changes.