I'm in a similar situation to Moggiee so permit me to answer from my memory of my last flight.
In the event of landing on water please evacuate the plane via the overwing emergency exits. Should the front exits be above the waterline and if directed by crew then these can be used.
Given I normally sit close to the front I'm not overly bothered about the rear exits as if the worst comes to the worst many pax behind me will already have found their way out (or not as the case may be).
I too extend the courtesy to the crew of at least listening to their messages and feel it's the least that people can do.