I've been running LimeWire Basic 4.9.29 with no trouble until tonight when it suddenly stopped responding to my clicks. I couldn't click on any of the buttons. I could use the keyboard to start downloads, but I can't use it for anything else. I don't know what's going on, because it's highliting the buttons when I hover over them, but when I click, nothing happens. Does anyone have a clue what I can do?

2 options:
1. Close & reopen to see if it does the same thing.
2. Try deleting your LW Preferences folder whilst LW is closed; instructions here: Fixes for Limewire

If still problems after that, it might be related to the version of Java you're using. If you're using Java 1.4.2 then install version 1.5 or if you have 1.5, then uninstall it using add/remove control panel & install 1.4.2 instead using the techniques suggested in the above link.