Well then, if the setting for MenuBar is (default) then that means the default
menu bar will be displayed.

A MDI application like Access needs to have "some" kind of menu bar.  You can
create your own that has no menu items in it, but having NO menu bar will cause
problems.

Most notable is that if you maximize any object in the Access window the buttons
that allow you to Restore, Minimize, and Close are positioned in the main menu
bar.  If there IS no main menu bar, then once an object is maximized the user
will be stuck there.  In the case of forms you can provide your own buttons, but
if it were a query or report then the interface offers nothing to the user for
getting out of that view.