A frame in a frame

Are you a techie? I want to combine two video signals – one shows players in a couch, the other shows on-screen game action. And I want to do it with a minimum of post-recording hassle (I don’t care so much about the complexity of the set-up).
Right now, what I’m going for is two cameras – and then synching the two signals in Premiere and showing both signals at once in the final movie (as shown in the illustration).
If anyone has better ideas I would just love to hear them.