|Just to be clear, you plan on formatting your hard drive, and installing Windows Vista on it. This will delete EVERY THING on the computer, and you will basically be starting from scratch after the Vista installation.|
The best way to backup your files (which you want to save) for a operation like this is to just copy and paste them to another location (other than your hard drive, which will be formatted). You could use a USB flash drive, another computer, etc. The other option would be to burn the files to a CD/DVD, but you will need a CD/DVD burner installed in your computer to do that.