My desktop is running Maverick updated from Karmic updated from Jaunty updated from Intrepid.

Back in the days of Intrepid, the gnome menus were not particularly well organized in my opinion, and so I extensively customized them. However after four updates these customizations have not fared well and the menus have ended up in a messy state. There are broken links to uninstalled software, duplicate links and menus, new links appearing inside unselected menus, in short a complicated mess.

Is there a quick and easy way to reset the gnome menus to a default state?

I do have a couple of customised launchers to specialised software, but it is probably easier to rescue those individually and add them back into a fresh menu than it would be to repair what is currently there.