Pretty strange your problem......
As for deleting the LW preference folder, well, it's actually quite easy and doesn't take a lot of time. It is also a precausion step to make sure that a possible corruption of it can be excluded as probable cuase for any problem. Read here on how to do this:
http://www.gnutellaforums.com/showth...threadid=36420
You might also consider to update your Java installation. Delete all Java from your system (START>Control Panel>Remove Software>Java), reboot, and then download the JRE offline installer of the newest Java version from here and install it (and reboot again afterwards):
http://java.sun.com/j2se/1.5.0/download.jsp 