I find theatre in the round (or semi-round) unsettling. In a normal theatre the proscenium arch acts as a barrier, it safely demarcates the world into them and us, and so yes, it does become a bit more like watching the TV or a film. And hence I find I can actually get caught up in the action more, I can forget about the real myself in the real world and just live in the play. As soon as the stage pokes out amongst the audience one is aware of a sense of danger - the actors may approach, they may (worst of all) demand some form of audience participation. I have seen plays where cast members take seats in teh audience, where they address audience members individually and expect a reply - all of this breaks down the ongoing dream of the play and makes me aware of myself as a person and the actors as actors rather than the characters they play. I think this is actually the exact opposite of what the directors probably originally intended when they started performing in the round. I suspect they want the unease and to make the audience feel they are participating directly - but it seems as if they do not understand that that breaks the imaginary dream playing in our heads.

Of course, ironicaly if you go back to the Globe and the theatres of Shakespere's own time that is exactly how they were laid out - with the stage sticking out into the audience. I suspect that going to the Globe is a very different experience if you are a groundling (one of the people standing in the pit) compared to if you have a seat in one of the galleries where there is a physical rail of wood between you and the stage. I couldn't stand for three or four hours on end, so I will probably never know.

there was one family that just got up and climbed over the stage to get back to their seats after the interval. I did not think that was polite theatre.

That is an amazing breaking down of teh barrier between actors and audience! For them not to be conscious of the difference between stage and 'real world', even during the half-life time of the interval, is incredible. Did you by any chance notice who in the group lead the way? Was it perhaps a child - someone less attuned to the social nuances? Or perhaps they are just naturally rude and inconsiderate people who don't mind overstepping normal barriers for their own convenience. But I suspect that if the director was there he was very pleased (although I'm sure as you say that the stage manager was furious).

I've also been thinking about what you said a few days ago about how the experience of the play is now in memory, and slipping further and further back, and cannot be repeated. In many ways of course that is what one pays for - to have a temporary experience that is heightened in its intensity by the very ephemerality of its nature. Some things about theatre the screen can never capture. Did you perhaps notice how much more intense the fight scene was than any screen fight? I have found that to always be the case. It is partly because the eye can choose where to look, and has the full advantage of peripheral vision, plus you don't have the interference of background music trying to tell you what to feel. But it is also the visceral truth of real time - the fight is happening right now, in front of you, and anything could happen. (And indeed I have seen a stage fight where something went wrong and it had to be stopped - the disconnect of emotions was incredible.)