Unloading a movie without reloading my menu

Hello,

First off, I am a novice when working in Flash. Secondly, I have created a simple menu located here:

http://www.aimeeg.net/catalog.asp

When you click on one of the thumbnails to the left, a large version loads on the right. But when I click the “close button”, my menu disappears, and reloads. Can someone help me perhaps with an actionscript which will simply close the large pic to the right, but with the menu remaining?

Thank you!