Alright, I've got a big issue. I've had this install for a good 6 months, but I partitioned the drives so that the main system stuff is on one partition and the /home directory is on another. I'm not sure why I did it, but the pointis that I have a well-established and perfectly configured system on a 37G hard disk that is running out of disk space at 11G because the system is on that partition. Is there a way to merge the two partitions into one? Or to save the configuration files to a cd and restore my config that way?

You might be able to resize the partitions if you have gparted installed.

A separate /home is a good idea - but (presumably) 26 Gig ???.
Personally I would have thought 11 Gig was plenty for the Ubuntu "system" - this laptop is under 4.5 Gig (including /home), although I'm careful what I install.

I don't like resizing partitions, although gparted is reputedly very good. I use the gparted liveCD to resize NTFS, but have had less luck with ext{2/3}. Go figure.
Backup the /home, delete it, then decide how you want to play. You could try expanding the root partition then restore (a smaller) /home, but I'd probably add partitions, and move the big (fast growing) directories to their own partition(s).
Frees up space in the root and allows for growth. Doesn't (potentially) compromise your current system/data. What's not to like.
just needs a bit of planning and care.

My big problem is that I don't have another hard disk to backup to, but I do have a very large disk that I have total access to over a network. If I zipped up everything in the /home dir, could I login as root and unzip them back after resizing the partition? Root settings aren't in /home, but in /root.

EDIT: I forgot to mention, I'm using Kubuntu if it makes any difference.

Sure - can't see why not. I'm surprised Kubuntu even has a root user.
I usually do all these sort of things from a Knoppix (or similar) liveCD. Avoids all the problems.

OH, duh. Sorry, as far as I know, all the Ubuntu family distros are live-cd only, with an installer on that. I just remember logging into KDE as root in Mandrake ages ago. Ha, you learn a lot in a short amount of time, I guess.