GRUB can be started by LILO. See README.txt in the GRUB for DOS release.
GRUB and LILO always conflict with Windows. And GNU GRUB is not so robust, causing many problems during boot.
So try GRUB for DOS please. It is a cross-platform boot loader based on GNU GRUB. The GRUB.EXE can be started from DOS/Win9x; and GRLDR can be started from BOOT.INI of Windows NT/2K/XP/2003; and even more, the GRUB.EXE can be started from LINUX via the KEXEC tool.
By using GRUB.EXE or GRLDR, you don't have to touch your MBR. It is the safest way coexisting with DOS/Windows.
You needn't install GRUB for DOS. Just run GRUB.EXE from DOS, or append a line of "C:\GRLDR=START GRUB" into your BOOT.INI(restart and select the "START GRUB" menu item), that will do.
Download GRUB for DOS here: http://freshmeat.net/projects/grub4dos/
There is a fat12grldr.img file with the GRUB for DOS release. You can create a GRUB bootable floppy with this fat12grldr.img file.
Or, you can just copy GRUB.EXE to your DOS floppy and run GRUB.EXE to enter the GRUB environment.
If the system has no DOS/WINDOWS, you may use the bootlace.com utility to write GRLDR boot record onto the MBR.