Ok... so as a person with a degree in Fine Arts... Movie watching is more than a hobby.
So, I too cannot name just one.
Here is a sample of my favs: (yes I have many, many, many, more)
Star Wars (episode 4,5,6)
Spaceballs (of course!)
almost anything else... lol
The Goonies (wished I had friends/adventures like this)
Ferris Bueller's Day Off (wanted to be him when I grew up)
The Breakfast Club (some of the most amazing monolgues for teens)
The Neverending Story (cause who doesn't like a flying Dog-Dragon)
Horror: Not a big favorite of mine, but since it is SO prolific in the thread here is my perspective
The Hellraiser Trilogy (The best all around horror franchise out there, its got a "believable" story, gore, jumps, and even some well placed comic moments, it really is the whole package. Something you don't find often if ever in the horror genre)
Equilibrium (this gets no love, because it came out at the same time as the Matrix, but the bullet-time Gun Kata in this movie might even be done better.)
Shaolin Soccer (if you have not seen this, check it out!)
American Beauty (this is a textbook on cinematography)
Primal Fear (Edward Norton's best performance... PERIOD)
Phenomenon (A movie where you ACTUALLY like Travolta's character)
Powder (powerful story, well told and performed)
The Power of One (about the Aparteid in South Africa, awesome)
What Dreams May Come (not given the credit it deserves as a beautiful piece of art)
As I said, I could go on and on, but I will stop now for your sanity. If anybody is interested in having a deeper conversation about any of this, feel free to PM me!
Great Thread by the way, scrolling back up to click LIKE... NOW!