1) ESB
- best SW film. perfect from beginning to end. I always especially love that Yoda warned him off going to Bespin, and Luke achieved nothing there. But at the same time you could argue that knowing he was Vader's son at that time was better then finding out on the DS2.
2) ANH
- Love all the parts of this, from Tantooine to the Death Star to Yavin to the trench run, just a really fun adventure move. Sir Alex McGuinness & Peter Cushing are especially good.
3) ROTJ
- mostly great. Throne room scene is an all time movie fave of mine (YOUR FAITH IN YOUR FRIENDS IS YOURS). Jabba rescue is great. Ewoks are weak as hell, and the main detriment of this film. I really wish they'd have gone with Wookies.
OG trilogy would be my pick with ease.
For the other ones:
ROTS - Haven't seen it since the cinema, don't remember much about it to be honest. My feeling at the time was that it was the best of the prequels by a wide margin, but light years away from any of the OT.
TFA - Pretty fun film with very likeable leads in Rey and Finn. But the main beat of the story is ANH's, and ANH did that better. The film starts the resistance off from pretty much zero again which is silly.
RO - The group of heroes have zero personality. JEJ sadly can no longer do the Vader voice that well, and his talking scene was poorly written too. Tarkin CG could do with some work, Leia CG could do with a LOT of work. There's some cool stuff at the end with Vader fighting. I approve of killing off all the heroes too. But I would have liked to have been sad they died - since the film did an awful job of filling them in as people I felt nothing.
TLJ - This film has many issues. It has weird humour in it that is almost certainly going to age very badly - that phone call between Poe and the general made me cringe for example. The main plot was so-so, and the whole casino planet escapade was awful. The usage of Luke from a wider series perspective was pretty bad. Luke, just like Ben Kenobi, makes mistakes as a teacher and the galaxy is paying for it. Then he runs away from it, gets coaxed back finally, helps a bit and dies. Huzzah. Poe is an embarrassment the entire movie. I haven't rewatched it since the cinema so I may have forgotten, but didn't his actions cause a ton of deaths and never really get addressed? The whole Holdo/Poe plotline is so pathetically childish on both ends I don't know where to begin there. I'd say the First Order is winning because the Rebellion is headed up by children, but then I've seen Kylo and Hux. Snoke is some creepy (and not in an intimidating way) dude in a golden smoking jacket. That was a thing. Plot points from TFA get tied off in what feel like unnatural ways