Star Wars, Empire Strikes Back and REturn of the Jedi........hands down.
Without those 3 movies, You would have never had many of the others. Star Wars was one of the single drivers of special effects ever made. I think it was the first movie to utilize model ships that weren't on strings. HUGE jump in movie tech.
It was such a gamble that the studio actually sold it in a package with an X rated movies remake of Alice in Wonderland that stared that hot ass chick from Meatballs. She gets uppity on some folks. Awesome faux porn musical. Back when Porns were filmed like real movies with production value. Good stuff.
Those other Star Wars movies......garbage. Nothing but effects driven shitholes to sink money into.
I liked the first Indiana Jones, the rest were trash. The final one made me want to shoot a puppy.
The Aliens saga was pretty awesome. #2 being one of my all time favorite movies. Nothing beats the Colonial Space Marines.
Lord of the Rings was an amazing Trilogy. It had everything but at times, a bit too much of everything. I rank it number 2.
Matrix 1, great. Matrix 2, cool because of the Ghost Twins.....Matrix 3. Burn it.
Never got into the Godfather. Boring to me. I even went to a special screening of Godfather 1 by 99X's Man Club back in the day, don't remember any of the movie, fell asleep.
Back to the Future should be in there. Great franchise.