The business with 'phones and filling stations has been discussed before. A load of BS. like so many of the RF radiation hazard scares, it's whipped up by a lot of hysteria from those failing to understand what they're talking about. There have been quite a few papers published about igniting fuel with sparks caused by transmitters, and there are some British Standards on the subject, although I can't remember the numbers. At mobile 'phone powers, you can't get enough energy.
Those people too rude to pay attention to the safety briefing should be treated in the same way - rudely ejected. I just wish that the BA safety briefing video wasn't so annoying - that damn kid drops the damn rabbit every time! And I thought the Captain was there to ensure that the aeroplane went somewhere, not just for PAX safety!