Running Lubuntu 15.10 'wily', the path to the xml file which contains the menu options. It may be different for another version, but for those who are running what I am running, this is the location of the file to change the LXDE desktop context menu.
To change the "Terminal" menu item to run the lxterminal, instead of the default terminal, open menu.xml (sudo) and find the following block of code:
<item label="Terminal" icon="/usr/share/icons/hicolor/128x128/apps/lxterminal.png">
Change the block to:
Your icon may be located at a different path, depending on your version, but this example is based on my machine, so yours may be different.
You can create your own icon .png file, and set the path there, as well.
When you're done, just save the updated file, and then right-click on desktop, and select System->Restart Openbox. Select "Terminal" option under shortcuts, and Vala!