Try deleting LW's preferences folder when LW's properly closed. See point 3 here & also point 2 if you've used older versions of LW in the past (there could be a folder in either location).
Fixes for LimeWire
This will kill all of your settings within options, you'll have to go back through afterwards & reset things. If you're not sure of your settings, go through LW's tools > options & write them all down, so that you can reset things later.

What version of Java are you using? If you're using the latest Java (1.6.0_02) & have used it before this without any problems, try reinstalling it. Use the JRE offline installer & remove your current Java version(s) before installing.
Java SE Downloads

If you've just installed that latest Java when you reinstalled LW, try this older Java version & see if it makes any difference. Again, use the JRE offline installer & remove any other Java versions before installing this one.
Archive: Download Java 2 Platform Standard Edition (J2SE) 5.0 Update 11