Bind the windows key to Lubuntu start menu

I managed to just get this to work with 'Super_L', not 'Super'. Hope that works. You could also set 'Super_R' to do the same thing, if you have one.

Super_L worked for me

<keybind key="Super_L">
  <action name="Execute">
    <command>lxpanelctl menu</command>
  </action>
</keybind>