Didn't we just have this thread recently?
Well, I guess I'll make a list of good stuff to watch. (The top four are my all time favorites, the rest is in no particular order.)
2001: A Space Odyssey - Great science fiction film with brilliant shots. It's like an orgasm of pretty pictures, which adds to the rewatchability.
Blade Runner - Perfect setting and atmosphere mixed with a nice plot and fantastic soundtrack.
Brazil - Both humorous and serious at the same time, with one of the most spectacular movie endings of all time.
Pulp Fiction - Flawless dialog and cool plot presentation, quotable to high degrees.
Alien - Like Blade Runner, Ridley Scott pulled of the setting and atmosphere perfectly in this movie. The plot is filled with suspense and is interesting the whole way through.
Jurassic Park - One of those movies I like to put on every now and then. Easily Spielbergs best, it's a perfect mix of action, intelligent plot, groundbreaking special effects and cool settings.
A Clockwork Orange - Arguably Kubrick's second best film, the character of Alex really gets to shine and pretty much makes the whole movie.
The Shining - Suspenseful and with great acting, it builds the mood brilliantly through the whole thing.
Full Metal Jacket - While the first half is easily the better part of the movie, the second is still great with the long and drawn out suspension of the sniper attack.
Eyes Wide Shut - You're pretty much good to go with any Kubrick film, this one is not as good as the four formerly listed, but it's still a testament to his fantastic film making skills. It somehow manages to be thrilling the whole time, even though you have no idea what's going on.
Star Wars - A classic which everyone should've seen, there's not much to say here.
The Empire Strikes Back - Widely considered to be the best Star Wars film, and I definitely see why. The already established characters made the movie able to jump right into the action just as it starts, it also manages to throw in more variation than the other two films by dividing the plot in three major parts, instead of two. Combined with the expansion of the movie universe and darker plot made it an easy choice for best of the three.
Return of the Jedi - Perhaps the "weakest" of the three, but still a great movie none the less, which feature some of the high points of the series, primarily the final confrontation between Luke and Vader. While it does start of slow, the rest of the movie is just as great as the earlier ones.
Resan till Melonia - My choice for the best swedish film ever. A nice animated film with clever plot and dialog, while portraying a clear message of environmentalism without being too blatant about it. Might be hard to find, though, especially with subtitles.
The Lion King - Perhaps the best Disney film, and by far the best of the newer ones. It's a classic, and I expect everyone's already seen it, but regardless.
Bambi - The best of the movies Walt was involved in, the beautiful backgrounds and mellow tone really makes this one, and I found myself liking it much more when I was older.
WALL-E - Best Pixar film, it managed to be partly darker and grimmer than their previous ones, but at the same time with more heart and warmth. While it gets a little sillier at times, it still manages to keep the overall quality at the top.
Up - Another great Pixar one, more notably the earlier parts of the film. It does get a little bit too action oriented later on, but the overall presentation is great. Made lots of people cry, I heard.
Back to the Future - Likely the best movie about time travel, it's a great comedy with really fleshed out characters and cool premise. The sequels weren't as good, but they still hold up and provide a good and worthy continuation of the story.
Raiders of the Lost Ark - The ultimate adventure film, it's good action, nice plot and badass Harrison Ford all in one. Pretty much inspired every treasure hunting film ever since.
Taxi Driver - This one's basically just a long and through characterization of the protagonist, which holds up through the whole film. You really get to know Travis and sympathize with him.
One Flew Over the Cuckoo's Nest - Among Jack Nicholsons best performances, you really come to like the characters and it all leaves you with a happy feeling.
Moon - A great modern science fiction film, with a great plot that's held up by pretty much only one actor through the entire thing.
Donnie Darko - Perhaps a bit puzzling for some, but I find the mysteriousness and somewhat strange plot nice. I also like the sense of details, which support further rewatches.
Time Bandits - All straight up Gilliam goodness. An imaginitive and fun movie that I love just as much now as when I was a kid.
Twelve Monkeys - A really interesting plot that makes some good and clever twists and turns. Also features some good acting from the lead roles.
Fear and Loathing in Las Vegas - All straight up craziness, if you like amusing dialog and absurd situations, you'll love this one. Some might not see the strengths of the film, but if you like quirkyness you'll find yourself hooked.
Mulholland Dr. - A really complex plot with some very interesting elements, you might want to look up some film analysis of it after watching it, but even if you don't understand it, it still holds up.
The Deer Hunter - A very grim and heavy movie, but it does it greatly. The long drawn out scenes really help establish what's going on, as well as support the killing suspense of others, most notably the russian roulette ones.
Planet of the Apes - Despite it's age, this one still holds up. The effects and settings are mostly still good, and the plot is just as clever, even if you probably know the ending.
The Thing - Fantastic horror film with a thrilling plot and insane special effects.
King Kong - This one has aged really well, and it's still great and inspiring. It might not look as good today, as it did in it's time, but the action and events still holds up.
The Dark Knight - Probably the best superhero movie ever made, there was an insane amount of hype around it at its release, and it held it's promise. The follow up is easily the most anticipated movie of the year, and there's a reason for that.
Reservoir Dogs - Great dialog, clever plot and overall suspenseful, like any Quentin Tarantino film.
Kill Bill - I count both parts here, they should be seen back to back, like one long movie. The action is fantastic in the first one, and the way the plot continues in the second one is just perfect.
Jaws - A good example of Spielbergs talent as a movie director, the suspense is on a constant high here, and it's all through an interesting watch. There's some great scenes of dialog in it too, especially in the later part.
E.T.: The Extra-Terrestrial - Another classic that I expect that everyone has seen. The overall playfulness and masterful puppetry of this one makes it just as good as when you were a kid.
Fantastic Mr. Fox - This one is all about style, the visuals are gorgeous and just makes you wanna stare more and more. It also expanded on the original story in a good way, but what really gets me is how pretty it looks, while also having that cozy Wes Anderson feel.
Children of Men - The attention to detail and references in this one is fantastic, and it also has a really great soundtrack.
I should stop.