Sudbury Hall is a late 17th Century house, the country seat of the Lords Vernon (a hereditary peerage).
Sudbury is also home to National Trust museum of childhood. I don't have any pictures of the museum itself- it was packed. The displays range from the past to the present day, (it's very odd to find things I played with as a child in a museum) and there are lots of hands on parts. I really wanted to see if I could squeeze up chimney and experience life as a Victorian chimney-sweep, but unfortunately I couldn't get near it as hordes of children were queueing, probably for the best I was bound to get stuck. I can imagine the Hall will be very popular with school parties, so you might want to bear this in mind if you're planning a visit.
The main attraction of Sudbury are the stairs, they are covered in ornate plasterwork and murals depicting classic mythology. It would have been handy to have my Classical Dictionary with me.
Fun fact: a BBC adaptation of Jane Austin's Pride and Prejudice was filmed at Sudbury.
I wouldn't say that it was the best National Trust visit I've ever been on. There isn't much in the grounds, apart from a woodland playpark for children, this and the Museum of Childhood would make it the ideal place for a family outing though.