Casablanca
Back to the Future
Inglourious Basterds
Butch Cassidy and the Sundance Kid
Star Wars With Han Shooting First Dammit
Ordinary People
The Taking of Pelham One Two Three (1974)
The Adventures of Robin Hood
Shaun of the Dead
Butch Cassidy and the Sundance Kid
Princess Bride
Almost Famous
American Beauty
Moonstruck
Galaxy Quest
I see some movies others have listed here that I’ve liked a lot, but they don’t quite make my personal list of Best Movies I’ve Ever Seen, which is as close to ‘perfect’ as I am going to get.
Jaws is the only film I have ever seen where there is absolutely nothing you could change that would make it better.
Pulp Fiction is close but if you are going to put a Revels song on the soundtrack, “Church Key” is a better choice than “Comanche”.
I’m resisting the temptation to say “You call that perfect? Here’s all the flaws in your so-called perfect film.” 
That’s contrary to the spirit of the thread. So here’s my list:
Casablanca
Jurassic Park
Airplane!
King Kong
LOTR:FOTR
Here’s mine. Subjective as all hell all get out.
Saturday night fever
Grease
Lawrence of Arabia
Nights of Cabiria
Hobsons choice
That was on my short list for the shorter list. Glad to see someone gave it a nod.
It left me speechless when I saw it when it first came out, couldn’t stop crying, and it’s one of the few movies I can’t pass by if it happens to be on when I’m channel-flipping. So powerful. I know there is controversy around it, but for the story it tells, just… damn.
The Big Sleep
Mildred Pierce
Beat The Devil
To Have and Have Not
Best Years of Our Lives.
All that being said, Treasure of the Sierra Madre is my favorite. “Tampico, what a town!”
And that’s why it didn’t make my list. But otherwise, yeah.
Second perfect movie: Funny Face.
There are flawless movies, and there are great movies. The only titles that can claim both labels that I can think of are Meet Me in St. Louis and The Searchers.
Not necessarily Great but possibly flawless are:
Devil in a Blue Dress
. . . .
I reserve the balance of my time.
- Koyaanisqatsi
- Stranger Than Paradise
- Wag the Dog
- Crumb
- The Killing Fields
I love that movie!
Repeating the two I did earlier, my five:
After Hours
Dr. Strangelove or: How I Learned to Stop Worrying and Love the Bomb
Persona
Last Year at Marienbad
The Wages of Fear
I have two to start (hint: I see parts of myself in both of these main characters):
The Browning Version (1951, Michael Redgrave)
Ikiru (1952, directed by Kurosawa)
More to come, I suppose, as I think of them.
The Full Monty
The Ring
Chinatown
Vertigo
Shutter Island
In no particular order:
Casablanca
The African Queen
The Godfather
Network
American Graffiti
Strong contenders to be included, but had to be cut to make a list of only five: Sabrina (1954), and The Quiet Man.
My five are:
-You Can Count On Me - Written and Directed by Kenneth Lonergan
(Laura Linney & Mark Ruffalo in his 1st film, great character piece)
-Blade*runner (narration version)- Ridley Scott
(who I’m pretty sure DIDN’T like that version but hey! this is MY list)
-Pulp Fiction -Written and Directed by Quentin Tarantino
(nobody does better movie dialog & action)
-Monty Python and the Holy Grail - Michael Palin/Terry Jones
(funniest movie ever made, no contest)
-2001: A Space Odyssey - Stanley Kubrick
(for me, the one perfectly crafted film of all time)
Jaws
The Silence of the Lambs
Top Gun: Maverick
Pulp Fiction
Goodfellas