Umm, it seem someone did not bother to read the rules.. If your copy of windows is legit, yea, eh, um, then reinstall, use your legit key and then activate by phone.. If not, the above poster has pointed out one of many ways to get legit.. I'll point out another. http://www.newegg.com/Store/SubCategory.aspx?SubCategory=368&name=Operating-Systems
NONE of the XP activation "cracks" work anymore... at least not by themselves.
I had found a very elaborate multi-step process to "crack" the activation in XP a while back (yes I do run legit software)... and I did not distribute it.... it worked great for a few months and then Microsoft changed other stuff (adding the validation required stuff to download certain things) and it didn't work anymore.
If your software is legit.. activate it over the Internet. If it can't activate it over the Internet.. use the phone method to activate it.