onmouseover

Personally i would use div and spans to show the various layers of your menu style display.

The source shows 3 important bits :-

1) The CSS to show and hide the layers, intially set so all r hidden.

2) The javascript that does all the work of showing/hiding the layers when the relevant function is called

3)The html structure that is important is: -

 

     - The line above is the one that calls the showing/hiding function you could change this to onmouseout or something like that
    Paintwork
   - The hyperlink is just the style i used to show something clickable so that they had something to click on to display the layer.
 

  
     
  

 

     - The line above is the one that calls the showing/hiding function you could change this to onmouseout or something like that
    Paintwork
   - The hyperlink is just the style i used to show something clickable so that they had something to click on to display the layer.
 

  
     
  

As you can see the only thing u need to change is the number at the end of sub to ensure the js works correctly and u can have as many submenus as you like!!!
This code is compliant for all version 5/6 browsers that have javascript enabled.