We will be traveling with our family of 3 older children -- 20, 17, and 14. We have never been to Paris and would like some recommendations on what to do and where to eat. Please give us advice on if and how we should buy Metro passes and Museum/Paris passes. We are also interested in buying some large artwork of Paris scenes that we could roll up and take back with us, so please let us know some good places to look for that at a reasonable price. Thanks!