Nikos,
National Treasure was a fun movie, and perfectly OK for the whole family to see. A little Indiana Jones-ish, it's about a guy who steals the Declaration of Independence in order to save it from the bad guys AND to find the treasure who's secrets are encoded in the document. Good clean fun.
You might also want to check out "The Rookie," with Dennis Quaid and "The Greatest Game Ever Played." Both are sports movies (baseball and golf, respectively), and both are again perfectly OK for all to see. My kids loved all three movies.
Regards,
The Rookie was a great movie...
I just bought the Anthology of Clark Gable...A collection of five or six at Best Buy.