The GParted Live CD has served me quite well when it comes to rearranging drive partitions.
http://gparted.sourceforge.net/livecd.php
Of course, if that isn't a partition...
Assuming that you have some knowledge of the Linux command line, you can use the terminal there to mount the hard drive to /needwrite/fake, then rm -r /needwrite/fake/WINDOWS to remove it. (Careful!)
There is probably a better solution out there; I just use the live CD there because I have it already.
http://gparted.sourceforge.net/livecd.php
Of course, if that isn't a partition...
Assuming that you have some knowledge of the Linux command line, you can use the terminal there to mount the hard drive to /needwrite/fake, then rm -r /needwrite/fake/WINDOWS to remove it. (Careful!)
There is probably a better solution out there; I just use the live CD there because I have it already.