Is that lying awake wondering how to dispose of the coins, or the wife?
This might be of interest: http://www.bbc.co.uk/programmes/p0499cj9/player
I can't abide the modern "commemorative" pieces. They simply aren't coins as far as I'm concerned, but that's just my opinion.
However, without knowing what you've got, it's hard to say.
Keep what pleases you most, or alternatively, think about why you've been asked to downsize. Does it take up too much space? Is it all over the house? I'd probably be inclined to avoid downsizing by whatever means I could.