Teknologic, and others,
Thanks you for your comments and assistance.
I tried all the recovery and reboot actions suggested on my original Nexus 7 - but could not resolve the start-up and charging issue.
Contacted the supplier here in UK (Tesco Direct) on Monday (8 Oct) - and after trying a couple of suggested resets they agreed to replace immediatel - with delivery 'next day'.
Sure enough the new one arrived yeaterday (Tues 9 Oct) - no problems, and the faulty one was taken away.
Glad to say the new one is behaving itself and all items I had previously bought were there waiting for me when I had completed the set-up.
Yes - frustrating to have the initial Nexus 7 'die' on me - but big credit to Tesco Direct for very prompt resolution and replacement within 24 hours.
They get a lot of criticism at times but this is excellent service which should be acknowledged.
All OK now and enjoying the Nexus 7 very much.