Go to Paris, but don't linger too long there. Rent a car, and drive down to Chambord, home to the largest chateau of the Loire valley. It's in the middle of what I believe is the largest nature preserve in France. If you're looking for accomodations that are romantic and pleasant (but by no means luxurious), you can stay at a small hotel right in Chambord, directly across from the chateau -- unfortunately I don't remember the name, but I'm sure it's in the guidebooks. Fax them well ahead of time, and ask for the corner room on the top floor with a view of the chateau. Go in early-mid September, when the crowds have subsided but the air is still warm; at night you will look out your window at the floodlit castle and (if you are like me) think it is approximately the most perfect thing you have ever seen. Time your visit right, and you will also hear the sounds of rutting stags wandering around the grounds of the castle. :-) (FYI, the hotel in Chambord is probably the cheapest hotel I've ever stayed at in France -- perhaps 60 USD for a double room per night. It is old, and quite faded around the edges, but the location is pure magic.)

While you're there, go to dinner at the Relais Bernard Robin in Bracieux, some 7 km south of Chambord. It's a Michelin 2-star, or was as of about 2 years ago, and a splendid place to have a romantic (and extravagant) meal. They may also have guestrooms (I really don't know), if you find the hotel in Chambord too quaint.

Have fun!