Ok, first, many of the one's already listed I will gladly watch

To add, I am more into comedies
Top Secret!
Hot Shots 1 and Part Duex
Airplane 1 and 2
Army of Darkness
Stripes
Anything Mel Brooks (though Blazing Saddles is 70s)
The Wizard
Crazy People
The Gods Must Be Crazy
Labernyth
Brewster's Millions
A Million to Juan
Ghostbusters
Fast Times at Ridgemont High
Dazed and Confused
Planes, Trains, and Automobiles (well, anything with John Candy in it)
The Police Academies
The Naked Gun
Tim Conway's Dorf series
Not sure if some of those are 70s or 90s. Go look at
www.imdb.com to make sure

And I am sure there are many more movies from that time I love.