I have vista right now and im want to try to use the ultimate or windows 7 on it but im wondering if i install it to my computer if i can go back to my old vista. Both that im trying to install are boot
you can always dual boot with vista that way it wont touch any of your files on that OS and all your files and everything would be safe. just partition your hard drive and install windows 7 and when you boot your computer just choose which OS you want to select