What he said
Change Bios to boot from CD
Put Windows CD IN Drive
When go through the Windows Setup you will be ask to choose the Partition
You will have to delete the one that already exist
Create a new one (I Created Three Two 20 Gig for XP Pro and one for Media Center or XP 64 and the third is the 110 for Data)
I have read that you need to install the Older one first and that 2000 and XP have to be on there own Partition. You may have to put 98 on the Primary...