Vista and XP Partition Error

[earwax_man 18]

Okay, I know this isn't on sc4; but it's really annoying

Okay, my pc came installed with vista home premium; but I kept vista on it for a while. Then today, i tried to dual boot both vista and xp, and it went bad. I formatted one of my 2 drives, for getting about my recovery drive, and now my xp partition is only 130gbs on a 320GB HDD. How can i just remove everything on my computer? I tried using Vista's formatter, but to no avail. Please help me!

Also I cannot access the other drive in formatting

[screamingman12 30]

Use either the XP or Vista disks and do a clean install by setting the BIOS to boot from the CD drive.