I had the same problem, I had the problem with Suse aswell as Slackware 9.
During the installation i was not asked to install grub or lilo (as far as i know on suse lilo was automatically instaleld).
on slackware i was asked to choose the boot device, when i chose my HD's MBR, i got an error saying it could write to the MBR (im positive the MBR is clear cuz i cleared it using three different methods about 5 times).
when i chose the primary partition to boot the OS, well this didnt work either cuz this filled my screen with 1's and 0's.
and booting from a disk did the same. I don't think the slackware set-up even wrote anything to the boot option i had chosen.
what is another way to get around this problem, besides the one given in the previous reply - i.e. boot from the OS boot cd. - using this method would be a pain in the kneck.