Huh. It worked this time. I don't know if it makes any difference, but this time I was quitting from GNOME and not KDE.
I have a Dragon Lite Soyo motherboard, and I'm running Knoppix DVD 4.0.2
During shutdown, Knoppix always hangs when trying to unmount the filesystems:
When this first happened, I thought it might be because I was supposed to unmount my hard drive partitions by hand. So this time I unmounted it through KDE before shutting down, but it hung anyway. Knoppix works fine in all other respects.
Huh. It worked this time. I don't know if it makes any difference, but this time I was quitting from GNOME and not KDE.

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