To make it so that they only appear in Windows XP as one drive, you can go to Disk Management under Computer Management. Then right click on the drives, select "Change drives and paths", and then select a folder you want to mount the partitions under. The only thing is that the folders you mount the partitions to must be made before doing that.
If this is not what you want, you must buy partition magic. There is no other real way to do it to my knowledge.
In my computer, it will only show up as one drive.
A+ Core Hardware, Software Certified (May 13 2005)
the new beast...
AMD Athlon XP 3200+ Barton running at 2.16 Ghz.
GeForce MX 4000 (mainly takes the load off the main system)
Creative Labs Audigy 24-bit sound.
Some Case from tigerdirect
512 MB Ultra DDR RAM.
80GB Seagate HDD
LiteOn CD-RW / DVD ROM drive.
currently looking at a litescribe drive at staples, due to its ability to label the CD shortly after being burned.