if you would like flash to just go to the url when the movie ends then you do this..
* create a new blank layer(i reccomend always doing this for every single task) and name it actions
*go to where your movie ends and create a keyframe on the blank layer right above (or below)
*select only the keyframe on the actions layer
*open the actions menu
*open the global functions folder
*select browser/web folder inside
*double click on get url or drag it onto the actions screen
* you should see somthing like this
*now change that to something like this
>>>(yes you gotta type in http://www. and all that)
*close the actions window
*preview it with f12 or control/enter
now if i was clear enough for you to do that, your movie will play and then at the end it should go to that url. You can also specify whether it should open a new window or change the window that the vid will play in.