If you want to hear how real people speak in real situations, then documentaries are a good bet. If you want to learn different pronunciations, then films and series can help. I wouldn't use cartoons - the voices given to the characters are usually very contrived and unreal. No-one really talks like Homer Simpson!
Don't forget the radio too. Find a good English-speaking radio station and have it playing near you as often as possible. You won't be distracted by the pictures and the action, like you are with TV or films. Don't try to actively listen to it. Having it on in the background will help you get to grips with the rhythm and cadence of the language and, in the long run, you will find that you understand more and more of the actual language along with picking up the pronunciation.