No, to answer your queries they lived in towns. They would live in a castle if they needed protection (e.g. if a war was going on). I hope that answers your question.
The Castle was both a military fortress of war as well as household for the noble and his family. Therefore the castle served two different functions requiring both a military and a domestic staff....
Town criers were the news people of the day. They passed out the newspapers that told events that happened, They were basically the one man news crew of the medieval ages.