They were definitively solid, but so much of it comes down to age and perspective. I'm partial to the 70's: Shaft, The French Connection, The Sting, Jaws, Airport, Close Encounters, Star Wars (original), The Godfather I & II, The Exorcist, The Omen, Carrie, Dirty Harry, MASH, Network, Deliverance, Apocalypse Now, All The President's Men, Deer Hunter, Taxi Driver, One Flew Over The Cuckoo's Nest, Serpico... Oh, the glory of it all! That was a decade of great films.
For the 80's, throw Airplane, Raging Bull and Scarface onto the pile!