DROP DOWN BAR stays down randomlym - help

The problem:

I made a flash bar composed of 6 buttons and 4 drop down menus, one next to the other, does anyone know how can I have the drop down menu limit the on press “mouse down” so that it wont let you onto another button untill you are out of the first?

If you keep your mouse button pressed and move to the next dropdown, then release, both bars stay down

the bar is at http://dock5.com/bartest.html

PLEASE HELP ME THIS IS URGENT!