Couple of ideas for you, especially if you are going on a Saturday. Head straight down to Dinard, then get into a taxi to the centre. There is a wondeful market there on Saturday mornings, until about 12:00ish. You could then drop into any of the cheapish restaurants in Dinard, or for a really pleasant experience, jump into a taxi again for about 15 mins to Saint Malo. There are a few rather nice pavement cafe's there inside the walled town.
Another idea is Guernsey. Very easy to get to - just make sure you have a transponder, and give them a call before you get to their boundary. You will of course have filled in a flight plan/customs form and light aircraft movement form for either trip, so they will be expecting you.
If you go to Guernsey, there is a rather nice restaurant in St. Peter Port, called 'Worlds end' I think - a few mins in a taxi, and your guests will have a wonderful time - just don't let them get too plastered.
Give it a go, you will be amazed just how easy it is, and it will open up a whole new world of aviation experiences to you.
