When you hover over anything in Ubuntu Yellow boxes pop-up (Tooltips) and give you information. Personally it bugs me really badly. If you are like me; turning them off is really simple.

Note: the quotation marks are not part of the names.

First right click on the "Applications" button in the top panel, then click "Edit Menus". e.g:

When the menu editor opens click "System Tools". In the right column you will see: "Configuration Editor" Tick the box next to it, and close the menu editor. e.g:

Now click on "Applications" then "System Tools" then "Configuration Editor". Once the configuration editor opens click the arrow next to "apps", then click the arrow next to "panel". This expands the menus. e.g:

Now select the "global" folder. and in the right column untick the box next to "tooltips_enabled". e.g:

There you have it. Annoying yellow boxes gone :)