I'm afraid I'm going to kick off with the predictable (for me) suggestion: Paris has enough to see and do to keep you occupied for a month, let alone a week. If you're only there for a week, I would recommend not wasting precious holiday time simply travelling to another place and travelling back again. If you really want to get out of the city for a day or two, how about day trips to Versailles, Chartres or Reims?