Search for liquid layouts.
This is basically “intelligent scaling” of the flash movie to fill the browser window.
ie: topnav is anchored to the top of the window, footer is anchored to the bottom of the window; content is centered in the window.
Adobe has a fairly comprehensive explanation and tutorial on their developer site.
I managed to make the site bigger using the pixel dimensions in flash settings. However now it has made the videos (brought in externally) pixelated as if they have increased with the site - yet their coming in externally. Any ideas? Is there a way of locking the external film so the size won’t change???