Now this is pretty hard.... becouse most of this serie had at least one crappy movie in them. and if you have to decide on the best trilogy, all three movies must be good.
I for one choose Star WArs, becouse alll three episodes were well don, and at least one of them very very well done.
As for the others:
Matrix: I didn't see all of it. That is becouse I lost interest after the second one. And I sometimes feel that directors hide their mediocrity under special effects.
Rambo: Let's be serious
. well the first one was pretty decent.. but the others... Anyway, the exploding bow kicks ass
Mad Max: Man, I just love the second movie of this trilogy, what a feeling, what cool car chases.. excelent, existentialist movie. Reminded of the game Fallout. And the first part was also very cool. As for the last one.... what the hell was that all about?
Indiana Jones: I only saw Raiders. so shoot me
The Godfather: The first two... what can I say.. They can make all other movies in this list look like childsplay. These are trully the works of a freat director. To bad the Godfather 3 was..... well...let's forget that one.
Lord of the Rings: why don't we leave it some time to set, ok.... ?
another one: how about puting Kieslowski's "Three Colors" up there?