Home installation Lounge forum: Deleting existing partitions (re-installing windows xp)

Hi,

I have a Dell machine which originally had windows XP on it but it was subsequently replaced with Red Hat Linux. I would now like to remove Linux and re-install XP. When I insert the XP installation disk and start the process it shows 7 partitions on the hard drive. 6 of them are listed as being in an unknown format (I assume this is the Linux installation) but there is also 1 4Gig FAT32 partition. My question is what is this partition ? Can I safely delete it or might it contain some critical OS-independent part of the system like the Master Boot record? My original plan was to delete all existing partitions and create a single new partition for XP but I am nervous about deleting this FAT32 partition because I suspect it has nothing to do with the Linux installation. So does anyone know what this partition is? Is it safe to delete? It is 4Gigs in size (10% of the 40Gig hard drive).
One final thought, could this be a partition with a copy of the original XP installation which I could restore it from, this would save me going through the installation process from the CD. If this is a possibility how would I go about doing this?

Thanks,

Usjes.