Hi, thanks to Olaf Meeuwissen and others who responded to my request for help.
I was encouraged to continue adjusting lilo.conf until it recognised my three OS (RH6.2, Debian 2.2 & Win98). It is now possible to boot into RH and Debian but Win98 seems to have a problem still. I had tried using "install-mbr" and this seems to have damaged the boot record of Win98. Booting Win98 comes up with the MBR of install-mbr. I ran DOS Fdisk /mbr but that did not fix it. I seem to remember a similar problem some years ago which I was able to fix with Norton Fixdisk. I won't be home for another week so I'll just leave it for now. Thanks again, Tim