found it at DistroWatch:
If you don't like the default menu, (which I initially did not like and still have mixed feelings about);
Right-Click on "Bianca" on the Panel and select "Remove from Panel".
Bingo! It's gone.
Right-Click on an open spot on the panel and select "Add to Panel", scroll down and double-click on "Main Menu" or "Menu Bar"(which ever you like best), and Bingo! you have a new menu.
If you ever want the "slab" back, choose "Linux Mint Menu".
It's that simple. You have 3 choices.
I personally keep the "Linux Mint Menu" and "Main Menu" on my panel, so I can go either way I like.
The "Menu Bar" is identical to Ubuntu and most standard Gnome default menus.