You either have to use the media that came with the PC (I assume it's a brand-name PC, correct?); most of the time you have to create this media yourself as most OEMs no longer ship restore discs... OR... you have to get your hands on a Vista OEM DVD. The advantage to the restore media is that you don't have to input the product key or activate once the install is completed. With the OEM DVD, you have to input the key from the sticker on your computer and you will most likely have to call MS to activate it. Other than that, it should work.