Skins can offer unique interfaces, some have menus on the right, some on the top, some use sliding menus.
Try some skins and choose your style:
There are two 'types' of menus in MediaPortal, the 'main' menu, and often a Context Menu, sometimes called an Actions menu, which displays in most windows when you select an item and press F9 or the Info/More remote button.
Main Menus are are available on most screens in MediaPortal. Sometimes they are visible right away, sometimes 'hidden' or accessible by pressing the left or right arrow key.
The first three options are 'standard' on most MediaPortal menus: