enlarging selections...?

Hey, guy's. Got a n00bie question here. I've tried and I've tried and I know I've done it by accident sometime before, but now I'm just not able to do this...

I've got a pic of...say...my son. I place a pic of a transparent CD on a layer on top of the son. I select the cd (that is a circle selection...heeee) and I now want to sort of magnify what shows of my son within that selection...

It is so frustrating when you know you've done something and you can't do it again. I think I've tried everythin, but no luck. Can anybody help me ?

I would copy the layer of the son, and size it up with the usual CTRL+T, then CTRL+click the CD-layer for the selection, and inverse the selection and hit DEL, while working on the zoomed-son-layer.

I do thank you, Finn-man

finn powa. paavo is da man.

alternative:

once you got the circle selection you can switch to the other layer, right click (windo$e) on the selected area and copy, then resize the new layer if needed