My input into this delightful debate is the Chateau de la Tour, about 25 miles North of Paris:-
http://www.lechateaudelatour.fr/site_anglais/main.htm
I visited this elegant turn-of the century French Chateau during the summer, for lunch with a supplier.
We sat down in the warm sunshine on the outdoor terrace, and surveyed the 12 acre park that openend out below us. The birds sang overhead in the mature trees and the scene was set for the most memorable meal I've ever had !
Not a particularly expensive location, about $35 per person for lunch, including wine ! For this minimal outlay, we were treated to five of the most diverse and orally sinful courses over a decadent 3 hours ! The French really know how to "do lunch" ; )
Do have a look at the website which gives a real flavor

(pardon the pun) of this stunning location, which I will definitely return to for a holiday next year !
( It shows sample menus, weekend packages etc.)
------------------
John