Leighton Hall. Never heard of it? Neither had I until I went there the other day. I'm not a huge fan of visiting big houses and going "Ooh look how the rich folk lived!" Always loved Wollaton Hall in Nottingham for that reason - 16th century mansion designed like a Venetian palace now owned by the council with a large stuffed giraffe in the hall (it's a natural history museum). Free admission, too, in a huge piece of parkland.
However, round here we do have a couple of places - Holker Hall. Pricey but no roped-off bits in a real home, and a fun little car museum and very good restaurant. Leighton was even better - you can sit on the furniture (and some of it is 18th century, made by the Gillow family who once owned the place.) It's still a home too. You get a tour, but it's all less pretentious and less commercially savvy, and that makes it all the more fun. The birds of prey display at the end was fun too, with sundry gruesome bits of meat being fed to pacify the fiendish creatures!