If you have everything backed-up try reinstalling by following these instructions- http://windows.microsoft.com/en-US/windows-vista/Installing-and-reinstalling-Windows-Vista#section_3
I need to reformat a dell that has windows vista. I have the cd's and I reformatted it before, but I must have sent it to the wrong file because it used up a lot of the disk space in one folder. The space was so small that even web pages would not show up in the right format. Which folder do I need to reboot to so that I still have room?

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