I've now seen the first two; 'The Birds' & 'Family Plot', thought they were pretty good, especially 'The Birds' and whats nice about all of the DVD's is it comes with 'the making of..' (in the special features), which guides you through the whole film and shows you how things were done and the reasons why shots were used and stuff.
This clip is from the documentary on 'The Birds' which i thought was a very good point.
(Video seems to be out of sync with the sound on my computer?!?!?)
I watched the film first, then the documentary and i to thought nothing of it, i just believed he opened a real door.
So we have Sound (although it didn't mention sound, there was a door opening sound which leads you to think a door is really there) and lighting to thank for that!