An update with good news:
With grateful thanks to a PPruner I received a link to 'get_Iplayer' (essentially written for Linux, and which downloads the Iphone material by 'simulating' an Iphone) which installed fine on Win7, and allows scheduling and recording of IPlayer stuff in MP4 format like a PVR. I also then found an open-source burner, 'DVD Flick', which (somewhat slowly!) converts MP4 to DVD format and then burns to DVD.
Job done.