Unloading a swf

hi,
i want unload (close completely) an intro section when i click on a button to naviagate to another section. The intro section is a separate swf file and i when the button is pressed to proceed to the next section, it opens an external swf file.

I have tried a few unload movie codes that i have found here, but the intro screen still flicks up for about a second when buttons are pressed to go to other sections.

Any help would be much appreciated, thanks!