Flash Website pop ups

Ok im making a flash website, and I want there to be a seperate pop up window when you click on a button.

Basically, you clikc on a button and it opens a seperate page that is 550 x 400 pixels that has an animation i have made in it.

How would I go about doing this? I guess the easiest way would to make a seperate page in Dreamweaver and link to that, but how would i specify the pages size in dreamweaver?