Can the mega-menu be disabled? Where do I go?

I updated from 1.2.5  to 1.2.9 and realize that the second level menu  is not  a regular “Page” but a “mega menu column.” When I unchecked “Check if you want to use this item as megamenu” it still defaults to a mega menu column. How do I go back to how it was in 1.2.5?