OK, this is weird.
After restoring files, I went to look at the blog... and found that the right hand column had gone missing, aside from the Free Software Foundation link.
I tried creating a new user on my system that would have a freshly-created profile. Same thing. I upgraded to Firefox 3.6. Same thing. I tried a different computer. Ditto. I tried Opera. No change.
The only way I can see my blog in its entirety today is to use Chromium (the Linux version of Google's Chrome browser).
Time to go seek out help from Blogger.
There is, though, a bright side to everything--it motivated me to back up my Firefox profile and restore just the important pieces of it. Now it renders the middle column nice and wide, as Chromium and Opera do.