My second option would be to leave the Windows boot manager intact, and boot Vector with a floppy or the install CD. I would prefer using a floppy if I go this route.
So I guess you have a floppy drive. They're getting rare these days.
Booting from a floppy works fine. Only one of my computers has a floppy drive. It's the one I use for beta testing upcoming VLs until they get far enough along that I can trust the VL being tested for my other computers. When I install a new beta or RC version I always put LILO on a floppy and boot with that when I want to run the version I'm testing. It also shows me whether it'll detect other operating systems without finagling.