Clicking quickly and repeatedly on a button

I want to set a button up so it is activated and it’s function runs completely before it can be activated again. I have tried a ton of things, but I can’t get it to survive multiple clicks. The swf does everything great so long as I click slowly but kids are going to use this and they will be clicking like crazy. I need a very basic example of how to set up and event listener and it’s associated function such that the FLV player associated with it can change it’s source and be ready to play the new source file before the source can be changed again by the next button click or better still only one button click is allowed until everything is ready to play and any other button clicks are disreguarded.