From what I know, there always seemed like there were two parts of the Fifties, culturally speaking. The era represented in BTTF 1 was the more vibrant part, with malt shops, explosion of teen rebellion, James Dean and Elvis.

This is around 1954/55-'58.

I've always thought 1959-'63 seemed like a "quiet" era of diners, slower ballad love songs, and JFK-era innocence. In fact, I'd say the Fifties ended when he was shot (and the Sixties officially began when The Beatles appeared on Ed Sullivan the following February). This was more like "toned down '50s".

Which do you like more?

I think the first part is more exciting (I'd rather go back to that era if I were time travelling), but I've always sorta had an interest in the second one. It was really like the calm before the storm, since the rest of the '60s changed at such a intense pace. Not just pop culturally, but with social and American political history. In many ways, the '60s was the beginning of the "modern" era.

I would prefer living in the second part, the more quiet toned down part.