I'm still scratching my head!
I've watched this mish-mash of a film countless times, and I'm still no further forward as to knowing wtf is going on! And all of you arty-farty types that think you do, well you're talking out of your rear-ends.
BTW, when Bowman opened the outer hatch door when he was in the pod .... why didn't HAL close it again?!
I've seen things you people wouldn't believe .........