Hidden Partition in Windows XP

[mzilikazi]

It sounds like you've created two primary partitions (disregard your Linux partitions for the sake of this discussion), the one WinXP is on and your FAT32 partition. However, unlike Linux, Windows can "see" one, and only one, primary partition per physical hard drive.

Really? Windows is that stupid? What will they think of next......

Anyway...to the original poster, just don't touch your XP partition and you should be fine. The GUI partitionig app on Knoppix is Qtparted. Launch it from a terminal as root:
sudo qtparted

Of course there is always good-ol' cfdisk (my favorite).