One of the most common questions I see in" install" and "newbie" forums, is people wanting to install windows AFTER they installed linux. I have always ( for dual boot ) just left windows alone and made a partition with gparted and installed liunx, maybe if people knew that before hand they would have an easy time, but then again, maybe some people only come to linux forums after they have nuked windows and are starting at that point. I have never installed windows ( don't plan on it ) but have heard it's kind of difficult.