"I'm trying to be good and make a boot disk and rescue disk of my SuSE 9 installation..."
I used to run SuSE but switched to Fedora. You can make a boot floppy on SuSE using Yast. That is apparently not working for you so I'll explain how to do it by hand.
Log in as root. Mount the first SuSE install CD. Put a blank floppy in the floppy drive. The boot floppy image is at /media/cdrom/disks/bootdisk assuming that SuSE did not change the name in SuSE 9.0. The best clue is that a boot floppy image is always 1.4MB in size. SuSE also has an explanation of how to do this in /media/cdrom/disks/README. To make the image use this command:
dd if=/media/cdrom/disks/bootdisk of=/dev/fd0
" is it still necessary to make boot and rescue disks, or is the rest of this just an exercise in futility?"
Boot disks and rescue CDs are real life savers when you have major system problems. Also you need to keep backups and be able to restore the backups using the rescue CD. The boot disk is extremely handy to have when you destroy your bootloader.
I highly recommend that you use LifeBoat to create a rescue CD: