I have 2001 in Laserdisc (the Cirterion box set supervised by Kubrick himself), DVD and BD...of course , I know it by heart and it was still very thrilling seeing it on the big screen. It is one of my earliest memories as a child-Mom taking us to see this in 1968- I especially remember the close up on Dave's eye as he was travelling down the "wormhole"..
As I mentioned, the sound was muddy, although separation was good- it IS an old movie ,but they could have done a better job..
Regarding the "digital cinema", I was talking about it with a workmate and we both agreed that the problem is that the projector uses a different light which , for now is not as bright as the old film ones, and obviously , the fact that it's projecting a digital image with LEDs(I may be wrong) will NEVER be the same as a bright bulb behind a strip of film.
STILL, the colors were quite good, it's just that the definition, brightness, contrast etc. is way lower than film.
(EDIT: IIRC , the definition of 35mm stock film is about 2-3K pixels vertically, so, although a BD still comes up short, it'll getting there eventually)
As for Cinerama, I'd have LOVED to see ANYTHING with the 3 projectors but I was too young at the time...funny how 2001 , it's still credited as being in CINERAMA when it obviously wasn't, and IIRC , the aspect ratio is something like 220 , not 235 as normal Panavision , although it later states it was in SUPER Panavision.
Ahh, the special effects. Funny that it should be mentioned. Both 2001 and Interstellar have a LOT in common because their directors wanted realism. Look up how many things were REAL in interstellar and not CG.
As it is this chain of theaters shows a "classic" every week (with subtitles , thankfully, not DUBBED) and we'll see what comes next...