The Extended partition is Dell tools I think. Look in the bios to see if there is something about recovery area...
anyway, When you installed XP, do it from the CD and from boot. When it comes up, it will ask you about 3rd party drivers for raid and such. If this is on a Fast track controller, you will need to supply the drivers for the OS to see it. Also, You may need to deifine the disks operation on the controller at boot.
hope that makes sense. Good luck