I always recommend the Alfred Hitchcock films from the 40s & 50s, but especially the color films from the 50s, and ESPECIALLY Rear Window, which is a prime example of a perfect movie. There us not a bad movie among them; in fact, every one of them is at least an 8, and many of them are genuine 10s, including:

Lifeboat

Rebecca

Strangers on a Train

Notorious

Dial M for Murder

Rear Window

North by Northwest

The Man Who Knew Too Much

Rope

Vertigo

Pyscho