Reduce size of BootCamp Partition

Hi... I have just placed an order for a ReadyNAS-DUO with a couple of 2Tb spindles following recommendation of a couple of guys at my work.
I have a Macbook-Pro running Leopard. I currently use TimeMachine to an external USB disk. Have seen several posts on how to move this to the ReadyNas and it seems pretty straightforward. My question relates to my BootCamp partition. When I bought the MacBook, I set up bootcamp with an 80Gb partition with XP-PRO SP3. Have a few bits of key software installed including MemoryMap so I dont want to reinstall it. But I do want to reduce the size of the partition as I have approx 40Gb free within Windows and I'd like to make this available to Leopard. Can anybody recommend a procedure to do a backup/image (sorry, my old VMS background coming to the forefront) or a full partition backup to the ReadyNas please? I want to image Windows, then delete the partition (I assume this is the omly way to reduce its size??), then recreate it smaller, then restore the image - and have the whole thing bootable in the usual way. Ideally I dont want to have to spend any money on Windows backup software - but I would if I had to. Could I use windows backup?? Please advise.