I have only seen 'Doctor Strangelove' and '2001'. I prefer 'Strangelove' as the better movie experience. Sure, '2001' has more thought and visual qualities, but I've always preferred the witty and enjoyable over the deep and meaningful. Its just more entertaining to watch, and makes me want to come back more. Meaningful is just as important though.
'2001' is still the second best Science Fiction movie I have ever watched, rivalled only by Star Wars. I know its blasphemy to put Lucas *spit* in front of Kubrick (who, judging by these two movies alone, is a genius), but again, wit and enjoyability over deep and meaningful (I'm talking about the Original Star Wars Trilogy. There are no prequels or spin-off's).
Yeah, I've just removed all credibility I have. I'm off to watch more Kubrick...