pretty - what is it?

Most likely it's Amelanchier canadensis. The leaves are initially bronze and emerge just as the cream flower sprays open. Then they become green. In June there are little red berries like single hawthorn berries, the blackbirds love them and get quite acrobatic to reach the last ones. In autumn the leaves turn beautiful shades, as in the photo. All said, a lovely tree for the garden as it never gets too big and is pretty for many weeks throughout the year. Everyone should grow it, I do!

Having now looked at your next photo, it is Euonymous europaeus! Not as nice as Amelanchier!!

Thanks for your interest. I had heard of spindle tree (although not realised this was it), and thought it was a wild viburnum. This little tree has been extraordinary this year, really bright for a long time, it's just losing the leaves now.
If I leave it (I usually cut it back, although didn't last year) how big will it get? This is the first year I've noticed fruit, probably because of cutting it back! I don't know of any others nearby.