With the help of afisk, I also corrected the problem. Apparently, the problem is related to a really low value being stored for the height of the application window -- which makes sense given the solution posted above.

My own solution was a bit different. I deleted a hidden "limewire.props" file in a ".limewire" folder in the preferences folder. You can access this file via OS X's Terminal program. You can also use TinkerTool to reveal hidden files and folders, and then just drag it to the trash.

After I trashed this file, everything was fine, back to normal.