Boot the windoze CD. You need like a rescue mode thing. You should get a prompt like DOS. Type in
That will take lilo off the MBR. As for patitioning after that, you should be able to run fdisk from that same prompt. Make SURE you get the right drive though. Something like fdisk d: or something to that effect.
I'm not a windoze expert, see sig below, but since noone else would answer, mine may be better than nothing.
Hope that helps.