I still want to keep my multiple desktops, I want to disable switching desktops with the mouse.
(this makes a backup file so that when you think you've messed it up you could revert it back.)
and delete the lines which says;
Log out and Log in back again to see the changes!
if you've messed it up and want to revert it back;
Answer quoted from Lubuntu docs
As of Lubuntu 14.04, the config file format and answer is now slightly different from @SWrobel's answer: