Add/edit pages misformatted after changing theme

I’m using Firefox 3.0.10.

I recently upgraded two blogs to WP 3.7.1. Before upgrading I set the theme to default.

After upgrading I found that the ADD/EDIT POSTS screen was misformatted. Text in edit box was right justified. Buttons at the top right of the screen appear on top of one another. I tried Internet Explorer v6 and find everything is formatted perfectly.

I decided to try a different theme. That had it’s own problems with the ADD/EDIT pages so I reverted back to the default.

Now I have a new problem. The ADD/EDIT screen are unformatted. Everything appears in a linear fashion. All elements are left justified to the left margin and one just follows another. There is almost no format to anything. No different fonts or colors. No boxes. No frames. No graphics. The entry edit box is only about 3 inches wide and 2 inches high, on a 21 inch screen.

Not so good. Any ideas where I should be looking? I FTP’d a completely fresh copy of all the admin and content files, which made no difference whatsoever.

I’m hesitant to start completely over since these were existing blogs with years of entries. Did not want to risk losing data, although I do have backups.

Thanks,

Banyan