Go to add/remove programs & remove your version of Java. Now reinstall Java JRE using the offline installer (point 1 below)
Fixes for LimeWire
Delete the LW preferences folder (make sure LW is properly closed first), points 2 & 3 above.
Now reinstall LW using the offline installer (it will automatically uninstall the previous version)
http://www.limewire.com/english/content/support.shtml
See how you go with that