OK, new Flash user here and I am trying to get my head around the differences between ActionScript 2.0 and 3.0

I’m trying to add an Action to an invisible button that sits on top of my animated Flash banner. I’ve used the following script but can’t get it to work (‘link’ is my instance name):

function goHome (event:MouseEvent):void
var targetURL:URLRequest=new
link.addEventListener(MouseEvent.CLICK, goHome);

When I check the script I don’t get any error messages however when I publish it won’t link. Can anyone offer any advice?