Problem With In Flight Pull Down Menu Graphics

During a flight, when I use the ALT key and then the pull down menu, I have a graphics problem when FS9 is supposed to go to another screen in order to make any changes. For example if I choose "Select Aircraft" the Aircraft Selection panel should normally completely get out of the flight screen and come up surrounded by a black background. My problem is that I don't get the black background. The selection panel is superimposed over the view of the airplane cockpit (when in 2D mode) and the panel is not all there (all the buttons are there but not the rotating picture of the aircraft).Does anyone have any suggestions as to what is wrong and how to fix it?Thanks in advance.Mike