Recent action/adventure films have raised the bar so high that older films almost inevitably pale in comparison, as I learn when I try to get my teenage kids to watch the great films made when I was their age. Seriously, considering - Lord of the Rings - Harry Potter - Avengers - Transformers - I will stop but the list is hardly started - then the older stuff can really seem boring.
And the animation in the last couple of decades is beyond breathtaking. For personal favorites I will name Shrek, Wall-E, and Finding Nemo but that hardly scratches the surface.
Even marginally older films like Jurassic Park and Terminator 1&2 make yet slightly older works like Blade Runner seem primitive.
I particularly like weird comedy/drama/satire such as The Fisher King and Spinal Tap, but that is just me.
Going back to the 1950s/60s/70s European avant-garde, that was my great awakening. La Strada, Last Tango in Paris, it just doesn't get better than that.
And I do like more marginal off-the-wall films, such as Satyricon and El Topo from back in the day (Jodorowsky's Dune would have been the ****), and Pi, The Believer, etc, from more recent times.