When I got a new computer, I installed Ubuntu and Windows XP on it. When I turn it on, GRUB shows up and lets me choose between the OSes. All right so far.
A while later, I decided I don't want Ubuntu anymore (Linux fanboys, refrain). I deleted its partition, but I realized too late that GRUB depended on it, so the computer wouldn't boot. I installed Ubuntu again and it's working fine. So how do I tell the computer that I want it to boot directly into Windows?