When creating a website, you should be concerned with what is on the menu, how it is structured, and if it is accessible so that everyone can use it. Some people use no mouse and must rely on how the keyboard navigates through the pages, so keep the focus in focus — you an see the action using the TAB key. Having rollover code that is also defining the action of the Focus is a good practice. If someone is using a voice input technology, then making clickable icons large enough for voice-controlled mousing is a must. For those using screenreading software do not use html semantic markup in the menu, use that instead for the headings in the actual page. Links are good enough for the menu.
For an example of a stellar menu design, look at the University of Washington website. The menu system is right on! Federal 508 regulations have helped guide the course of university and government web designers in the right direction. If you want to know what’s on the menu for access on the web, properly semantic markup, structured content and a well designed menu systems are a great place to begin!