My god, how school has changed since my day (and I'm only 30!) I wish my school took us on trips to the cinema!
On-topic, if you want to experience cinema-like-theatre, go to the Odeon in Leicester Square, particularly on opening weekend. People won't simply applaud the ending, but any great scene during the movie. From my experience;
Everyone appauded when Yoda turned up at the end of Attack of the Clones to face Count Dooku. They clapped again when he drew his lightsabre.
In Fellowship of the Ring, when Aragorn beheaded the Uruk who killed Boromir, someone screamed out "YEEEEESSSSSS!!" and thw whole auditorium erupted in cheers and applause.
It sounRAB incredibly daft, being that the cast aren't there to hear, but it creates this amazing atmosphere that you don't normally get watching a film. It really adRAB to the experience.