Is there a legal way to re-install windows XP without the cd but I have the cd key. I would like to download a legal ISO image but I can't find one. There is no image of windows already installed on my computer by the way.
unless you have a MSDN developer login, you won't be able to find those ISOs "legally" (or directly from Microsoft). Just download one from "disreputable" sources, and install using your CD key. Nothing wrong with that, as long as you don't crack the OS, or are using a stolen key.