Hi Sue
Thank you for the advice. I've now had another session looking for the box with arrows which enable you to minimise it away, and although I couldn't identify anything which matched that description, I did discover something which either wasn't there when I'd tried previously, or I just hadn't noticed it. Just below the horizontal bar which says "Home / Family trees / search / collaborate/ learning centre / DNA / publish / shop" was a narrow magnolia-coloured horizontal bar, and at the right hand end of it was the option "old search". I clicked on that, and Hey Presto, I have my old familiar screen.
Jean C