Maybe changing the compatibility mode might also have an effect. Right click the exe icon, go Properties>Compatibility and change it to Windows NT (or Windows 2000)
Otherwise I reckon updating your Java.
Uninstall LW and all Java versions on your system. Reboot and then download the JRE offline installer of the newest Java version from here:
http://java.sun.com/javase/downloads/index.jsp
Install it and reboot again, then reinstall LW.
