There is a TV Channel called "Talking Pictures TV" that shows old films and some old TV programs. It is available on Sky, Virgin, Freeview etc.
Many are films that have been "lost" for many years but now rediscovered and digitized to improve the quality.
They show films (UK and USA films) from a number of eras - 1920s, 1930s, 1940s, 1950s, 1960s, 1970s.
They also show TV programs from 1960s and 1970s, British and American (Bonaza for example!).
I am a fan of comedy and love watching some of the old comedy films from the 1950s and 1960s that I have never seen before. It is fun to find an actor playing a small part who went on later to be famous (Terry Scott, Tommy Cooper etc).
Because the films are of a certain era and often filmed in the streets of London, Brighton, Manchester etc it is also interesting to see what those cities were like in the 1950s and 1960s, as well as the clothes, the cars and so on.
I am not saying all the films are good and some have not aged well, but many of them are very interesting historical documents.
Sometimes they do put a warning at the start of a film or TV programs saying this was made in a time of different social attitudes.
Here is the web site for Talking Pictures TV
http://talkingpicturestv.co.uk/