[DanaC]

I used to use Camtasia years ago. That was pretty decent. I think there's a demo version floating about somewhere.

Might be above and beyond your needs though, and these days there may be freeware around that does the same thing. There's a 30 day demo available.

It was originally for making computer training programmes so although it does all sorts of other things, one thing it is very good at is just recording everything that is going on on your screen. Don't know how resource hungry it is. It used to be just about usable recording an ongoing mmo game, which is about as resource heavy as it gets. I seem to recall J using it a few times to make training videos and demos to show various parts of a design process.