I've had this problem before (and resolved it), but I can't remember how I fixed it...
I installed Debian on my laptop and added my Windows partition to LILO. I've used LILO for a couple of years, and I've added more than a couple of Windows partitions, so I don't think its the configuration. When I reboot and try to go into Windows, it starts loading, and continues loading for about 10 seconds before it spontaneously reboots. On occasion I can get into Windows with weird combinations of running LILO, rebooting, going into safe mode, rebooting, and then going into Windows normally. Any know how I can fix this? Thanks! Ben Pharr