how do I restore windows and uninstall ubuntu if I don't have a setup disk.
 

Hi I have a major problem. i recently installed ubuntu on my laptop and my desktop computers. Little did I relise that i accidentaly deleted windows off of the computers. I don't have a setup disk for either of the computrs. My laptop has windows xp but my desktop has vista. I desperatly need to get windows on my computers before my brother finds out. Also I want to completely erase Ubuntu off of the computers.

You should always double check what you are doing before you do stuff like this, and why did you install ubuntu on all the computers when you didn't know what you were doing?, you should always try stuff on a test machine of somesort. If you are lucky when your computer boots up there will be a message that says Press <somekey> to enter recovery, and if you didn't delete that partition too, it should work

# sudo fdisk -l
<your passwd>

post what you get to the list

If you chose to "resize" the windows partition during installation, you are probably fine.
Do what amani suggested, that way we'll know.
you need to go to applications - accessoires - terminal and enter the command there.