Zooming out effects

Hey guys!

I was wondering if anyone could think of the best way of presenting this:

i have a screen shot of a webpage on the slide with a presenter video talking about it in the presenter panel. When he starts to talk about a certain part, i would like it to zoom in a part of the page to see it clearly.

At the moment i have just cut out that part of the image, enlarged it and put it on top, and then remove it when he's finished talking about it.

What i would really like would be for it to look as if the cut out piece was zooming out of that part of the page. Can anyone recommend any animations that would make it look that way?

Note: dont think i can use the zoom/faded zoom animations in powerpoint as there is no control over where they zoom in from i.e centre (as far as i can see)

Also because of the video in the presenter panel, it needs to stay on this one slide.

Hope someone can up with some intuitive ideas! 

Many thanks