Could be a Java issue; you might want to try to uninstall LW and all your Java versions. Download the JRE offline installer of the newest version here:
http://java.sun.com/j2se/1.5.0/download.jsp
Install it, reboot and reinstall LW.
If that doesn't do the trick you might have to check whether any other protection program(spw/maleware) prevents LW from opening.
And as a last resort you could try to delete the Limewire preference folder as described here in Point #2 & 3 in Fixes for Limewire
http://www.gnutellaforums.com/showth...threadid=36420 