I personally will (although I loved all four books) wait until the film is available on DVD. Then I will be able to watch it on my own terms, without having to put up with noisy children, noisy crisp packets, foul smelling popcorn, mobile phones ringing, etc, etc, ad nauseum.
Until all these people can be made to realise they actually went to the theatre to see a film, not stuff their faces and have a chat with Auntie Edna in Cambridge in between typing out text messages and shouting at their kid who's just spilt its icecream all over their laptop computer, the optimum size for a film audience will be one!