Lubuntu keyboard shortcut for menu

Alt+F1 or Ctl+Escape are the keybindings for opening the main menu. All keybindings (as well as many other settings) are contained in ~/.config/openbox/lubuntu-rc.xml

I can't seem to find a shortcut for opening the navigation menu, but a list of keyboard shortcuts is located Here

Here you can download software that allows you to create of modify keyboard shortcuts Here (broken link)

You can install xdotool and create a keyboard shortcut that runs the command

xdotool click 3

...which will create a right-click event at the location of the mouse

...and create a global keyboard shortcut for it in your WM... here are some useful openbox references:

http://en.gentoo-wiki.com/wiki/Openbox#Create_custom_keyboard_shortcuts

https://code.google.com/p/obkey/