I have a question about re-installing my Windows 7 Home Premium on my ASUS laptop?

Ok so i have a problem, on my computer that i own now, i want to reinstall my opeating system in order to restore it back to new and to keep it at its best, and i downloaded my OS, Windows 7 Home Premium 64 bit from here a href="http://msft-dnl.digitalrivercontent.net/msvista/pub/X15-65733/X15-65733.iso" rel="nofollow"http://msft-dnl.digitalrivercontent.net/…/a and now i want ot burn it to a DVD and use the product key located at the bottom of ma laptop, will this work, or i do i need a special ISO image of it, like an OEM from ASUS (because my laptop is an ASUS X52F), will just downloading that image and buring to dvd and installing and puttin in the code work? i also would like to have this DVD as a backup just in case i was to ever get a virus. also this isnt illegal, as im using a legitimate product key, thanks in advance