A few of my favorites:
Amadeus
Monty Python & the Holy Grail
Heathers
This is Spinal Tap
To Be or Not to Be (‘83)
Wages of Fear
A Night at the Opera
The Piano
Psycho
Real Genius
ed: A few of those are from before 1975. If you’re open to it, I also recommend:
The Great Escape
2001: A Space Odyssey
Sunset Boulevard
Ace in the Hole