I don't know specifically how in DreamWeaver, but you basically do it like this (maybe it's a little off, my HTML is rusty):
<font face = "courier">
<FORM METHOD=POST NAME=form_name>
<OPTION SELECTED>Select whatever
<OPTION VALUE="the_link">Name of menu item
<OPTION VALUE="the_link">Name of menu item 2
</SELECT></FORM></font>
At least that's how I remember it. If you want an example of the autoloading JavaScript or seeing menus customized with CSS, you can go
here and do view source on the left frame (gray background).