Categories admin page missing

This is so odd. For the last few days, my categories page is missing. That is, if I click on Categories under Post, I see a blank page. If I click on Dashboard, then in the Right Now/At a glance box, I click on Categories, they all show up just fine. In fact, nothing appears wrong with anything else, just the categories page when clicked from Categories under Post.

Over at wordpress.org, I found this thread: http://wordpress.org/support/topic/165126?replies=15

It appears that a database table was corrupted for some of these folks. I have tried deactivating several plugins, first the WP-Sticky one mentioned, then the others that I think were installed around the time I noticed the missing categories page. Nothing has helped yet, but I haven't tried repairing the table.

I did let mySQL check wp_posts and it didn't show a problem. Then I did a screen cap of the structure. http://www.larchmontgazette.com/postcat.pdf
Is that how it should look?

And here, it looks like there are no categories for these posts, yet they show up fine on the site.
http://www.larchmontgazette.com/postcat2.pdf