Coombe Abbey ?
http://www.coombeabbey.com/
It is east of Coventry and very near Birmingham.
As you can see from the name, it is not a stateley home but an old abbey, but it has a beautiful hotel complex built alongside it so ideal for guests. Many rooms have 4 poster beds and olde worlde features.
In part of the Abbey they also do Mediaeval banquets (also open to the public).
Instead of the normal evening reception you can have the reception in the banquet. The bride and groom become the "king and queen" for the evening and there is much singing, bawdy humour and merriment. Its a great evening.
My wife's sister got married there and it has a fantastic atmosphere. We all had to get dressed up up in mediaeval clothes.
Example picture from inside
http://www.le.ac.uk/gl/conodont/ICOS2006/image s/Abbeygate.jpg
The banquet
http://www.ianbaldwin.com/Images/2006Photos/a2 5.gif