An international network of/for intelligent organisms
Answering my own question the Windows 10 built-in Video Editor, although very basic, appears to do the job.
If you want something more capable, Hitfilm express does a very nice job and so does Shotcut, I switched to shotcut because I can also use it on Linux, both enable you to pan and zoom around the shot a bit
I've since discovered OpenShot Video Editor which is pretty versatile but without all the bells and whistles of the two you mention. Quite similar to the old Microsoft Movie Maker.
(Envelope received. Ta Muchly :¬)