Replace one swf movie with another

Question

I have a flash movie on my web page and I have made some of
the text inside the movie into buttons. The movie only takes up a
portion of the page. I would like to replace the movie with another
movie when somebody clicks the button.
I'm sorry if this is a really basic question but I have spent
ages trying to find out how to do it and I keep getting an error
when I try to search this forum.
Thanks for your help.

Answer 1

Thanks for your help so far. I seem to be having more and
more trouble though!
I have a swf file (sunnyserv.swf) that contains a pre-loader
and then opens another swf file (downturn.swf). The downturn.swf
contains the buttons that I want to listen to, and swap out the
movies.
If I open sunnyserv.fla in flash and test the movie, it loads
downturn.swf, listens to the mouse click and runs the
communication.swf movie (although it doesn't clear all of the
children from downturn.swf).
However, if I export all three movies and open my web page
nothing happens! If I change the xhtml to load downturn.swf that
works ok. Any idea why it would work in test movie but not when
loaded into an xhtml page?
Also, can you see a reason why all of the children are not
being removed in the commClickHandler function?
Code below:
sunnyserv.swf (container)
var l:Loader = new Loader();
l.contentLoaderInfo.addEventListener(ProgressEvent.PROGRESS,
loop);
l.contentLoaderInfo.addEventListener(Event.COMPLETE, done);
l.load(new URLRequest("downturn.swf"));
function loop(e:ProgressEvent):void
var perc:Number = e.bytesLoaded / e.bytesTotal;
percent.text = Math.ceil(perc*100).toString();
function done(e:Event):void
addChild(l);
removeChildAt(0);
percent = null;
downturn.swf
import flash.events.MouseEvent;
import flash.events.EventDispatcher;
import flash.display.MovieClip;
var l:Loader = new Loader();
// add listeners for each button
btn_communication.addEventListener(MouseEvent.CLICK,
commClickHandler);
function commClickHandler(event:MouseEvent):void {
for(var i:int = 0; i < numChildren; i++){
removeChildAt(i);
l.load(new URLRequest("communication.swf"));
addChild(l);
stop();
Hope somebody can help!