Write the HTML for the menu's but place them all inside <div>'s which have visibility: hidden; set.
Then use onmouseover on your link buttons to change this value to "visible"
onmouseout is a little harder: you need a little delay before making the menu invisible again. If you have SOME javascript skillz this should be a piece of cake.
Otherwise you will have to find a script written by someone else...or ask me very kindly to write one for you. Which i will do...