when your computer boots up, bang on the delete key until you get into the setup screen...
find your boot options and make sure it looks something like this
1st CDROM
2nd HDD
3rd there might be something else here... who knows =P
make sure you save and exit CMOS, then pop the windows xp cd in...
when it's booting it will pop up a thing in DOS that says
Boot From CD-ROM: (it will kind of wait here) press enter when you see this
some computers you have to press enter, and some you don't, just press it to make sure...
at this point your computer will start the install of windows XP and you will eventually come to a point where you can format the drive (i use NTFS QUICK option)
good luck =X
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Aragorn Olafsun - Life/Bow LC
Frion - lvl Battle mage LC
Mindgame' - DT
Burning Vitae - DT