Why don't you breifly describe what it is you're looking to do. I'm not sure what you mean when you say this person "switched" their XP system to one with OS X. Like, was it just some sort of cosmetic change in the form of an OS X-like theme for XP, or did this person buy a Mac?
I don't know if anyone saw the video on CNet where Veronica switches her Win XP to OS X Tiger. Well...anyway, I wanted to know if this was reversable. I also wanted to know if you can still use Windows XP applications on that (or does it need to be in Mac format). I also wanted to know if you can do this on a desktop computer. If anyone can help me, please respond. I really want to do this, but I don't know if I want to if I can't reverse it.