A program like partition magic can do the job, but there's no utility in windows that lets you convert from NTFS to FAT32. You can only do the opposite (according to Microsoft, but again, partition magic, and maybe others, can do it).
Since your only interest is data, one thing you could do is use RedHat to transfer your files. I'm not sure if RH has NTFS support, but I'm sure it's possible to install it. From there, you copy everything you want to keep in your NTFS partition to a temporary directory, then you create your FAT partition, and finally move back the files there (since Linux has full read/write support to FAT).
That's all.
Edit : I realised that you can't actually access the partition. I'm not sure in Linux, but one thing you could do is boot from the XP cd. From there you can access a simple comand line, and I'm quite sure you could format the partition from there, and maybe create a FAT too, but I'm not sure on the last part.