1. Reinstall Java. Use the JRE offline installer here. Remove your current Java version before you install the new one.
http://java.sun.com/javase/downloads/index_jdk5.jsp

2. Delete LW's preferences folder when LW is properly closed. See points 2 & 3 below. If you've only used very recent versions of LW then the folder will be in point 3's location. If you've used much older versions in the past, there could be a folder in both locations.
Fixes for LimeWire
Deleting this folder will kill all of your settings within options...you'll have to go back thru & reset your options afterwards.

3. Now reinstall LW & make sure to use the offline installer (not the recommended one).
http://www.limewire.com/english/content/download.shtml