Help on Pop up menus

Im having a problem creating a pop up menu in dreamweaver. Ive been working on
it for a couple days now and its not working like it should. When im in
fireworks i can use the slice tool and drag the pop up menu to the destination
i want. But when i try and do this in dreamweaver i cant. The only way i can
get the pop up menu to my destiantion spot is by using the x and y axis but
when i preview my page the x and y axis changes when you minimize and maximize
the page messing up my destination spot. Can anyone help me out or tell me an
easier way of going about doing this?