Add Drop Down Menu to Navbar??

[DarkWarriorXII]

Hi I'm able to add regular links to my navbar, but I was wondering, how do you go about adding a drop down menu? I can't figure it out. In the links for the drop down menus its says stuff like:

accesskey"4"

How do I create a new accesskey?

It also says:

<script type="text/javascript"> vbmenu_register("navbar_search"); </script>

Should I just replace "navbar_search" with my own or what? Thanks for any help!