Menu button question, ezee:)

I thank thee you good soul reading these words for an attempt to resolve my small puzzle;) My question concerns a menu button I am struggling with: I have a menu MC with tweening buttons - a button loads a couple of movies but when they load I would like to make the button inactive somehow so that when someone clicks it twice accidently - it does not load the whole thing again. It surely have been posted earlier but there are about 335 thread pages with buttons so forgive me if I repeat the subject. Thanks:)