To cleanup the Windows.old folder, you can click on the Vista pearl, type "disk clean" and hit enter to open the Disk Cleanup tool. Choose "Files from all users on this computer" and choose the drive you want to clean. After it lists what is available
to "clean", scroll down and select Windows.old from the list of choices. Then delete as desired!
Thanks this saved up like 20 gig for me after reinstalling windows 3 times a year i never knew it was possible .