Bind the windows key to Lubuntu start menu
Solution 1:
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.
Solution 2:
Super_L worked for me
<keybind key="Super_L">
<action name="Execute">
<command>lxpanelctl menu</command>
</action>
</keybind>