Thanks to MS and DS, both of whom responded to my premature obituary for the Mac.
After a few frustrating days of trying to work on an 8.x" netbook, I hauled the Mac back out. It worked, and it's still working. I think it was a heat problem, even though I kept a dual-fan cooling pad running beneath it at all times. I'm babying it along -- using it for shorter lengths of time and actually shutting it down instead of just letting it suspend after an idle while, etc.
But, backup is paramount. I can't afford to be offline for even a day -- it's where I work!
MS sent me a desktop that had some problems (a tendency to reboot for unknown reasons). It's a great computer. Unfortunately, UPS banged it around so much in shipping that (despite an abundance of bubble wrap, packing peanuts, and even some oranges from the S family's own tree) the bay covers were all knocked loose ... and the thing won't power up. Not to worry -- there's enough good stuff in it, including 2Gb of RAM and two large hard drives, that I think I'll be able to cobble a working desktop PC together with some stuff I have here.
I'm writing this blog post on the HP laptop DS sent me. His description of it was: Wireless had stopped working at some point in a Ubuntu upgrade (more on that in a minute), and he didn't think the optical drive worked.
The optical drive did work. Because I had Xubuntu lying around, I went with that. Mistake. Wireless indeed did not work, so I plugged it in via Ethernet ... until the third boot when Xubuntu finally said "you know, there's a driver that will enable wireless" or something to that effect. And it worked. But after futzing around with packages trying to get Firefox from 3.0.x to 3.6.x, I gave up.
The thing is, every time I try to use Ubuntu (regular, K, X) it's just a huge pain in the ass. It's a solid distro underneath. I love several distros based on it (and perforce on Debian). Jolicloud (Ubuntu-based) is great, and I'd be using it if it supported this laptop, but it doesn't. I'm using another Ubuntu-based distro, Linux Mint, and it's fantastic. Easy install, easy upgrades/updates, detected my need for a proprietary wireless driver on the first boot. Love it, but I don't ever plan to bother with a distro ending in "buntu" again.
Sweet machine. AMD 64 dual core, NVidia graphics card, LightScribe optical drive. I could get used to this! Thanks, guys! Computer emergency over.