So it installed, it just doesn't know PPP or eth0 yet--I still have all the configuration to do. Funny how if you pronounce "eth0" with "aught" for the 0, it's "e-thought." Huh.
After a cup of coffee, I set about putting the case back on the routerbox. (Well, after I removed more casedust. Blech.) Since it's pulled out so I could plug the monitor in (the cable comes out the front of the desk, so it can plug into the Windows box that sits in front of the desk rather than under), and it was the first such time since the house had a digital camera lying about, I took some pictures.
The side that faces out under the desk, and the top:

The opposite side is blank except for the one Unamerican Activities sticker up at the top:

The front just has a couple stickers on it. The "GNU/Linux" one particularly apropos now that it's a Debian box, and the other was made with a label maker and sufficient boredom. (If you look closely, I have some symbol pieces in the magnetic poetry stuff. Those were also made with the label maker.)

Notice also the lack of a floppy drive; it is, like the same drive was in the other box, an internal floppy drive: you have to take the case off to put a disk in. Fortunately for this box, it's a lot easier to take the case off: both sides have panels that unscrew with these screws with enormous heads, so you can do it easily by hand. I'll probably leave this "front" side unscrewed, in case I need to put the boot disk in.
Removing the case easily was Compaq's one concession to expandability (that is, the cosmetic one). I thought I might've been in trouble during install because I've misplaced the floppy disk with the DOS program that lets you edit the BIOS settings (!!). When it was new, it had a hidden partition on the (650MB) hard disk with the program, but I upgraded the hard disk and so lost it.