Gparted is included in Live Cds like Ubuntu, Gnoppix etc. Most Live Cds have a partitioning tool of some sort
Fedora does have a Live CD but it is a serperate CD from the install one Fedora has a install CD AND a Live CD two sperate disks. Try the Gparted Live CD:
http://gparted.sourceforge.net/livecd.php
Check out the documentation for further hints:
http://gparted.sourceforge.net/documentation.php ,
but really it is as simple as deleting the Fedora Partition by doing Partition>delete then you can choose to re-format from the Live CD if you wish
then just re-install windows (you have an XP install disk right?)
Jake