Please bear in mind that these are generalities that I have observed and are by no means to be taken as statistics out of an etiquette book! :)
* In France, it is bad manners not to have both hands on the table (in direct contradiction to the American version of table etiquette)! Children are constantly reminded, "Met tes mains sur la table."
* On the other hand, it is NOT bad manners to put your elbows on the table. This is preferable to having your hands beneath the table, in your lap.
* In France, it is bad manners to put your portion of bread on your plate. It must be placed on the table next to your plate, except on very special or formal occasions when it is placed on a little bread plate provided for just that purpose.
* This portion of bread (and YUMMY bread it is too!) must be torn into bite-size pieces before being eaten. To bite directly off the piece of bread is considered eating like animals. (They have a point...)
* In France, it is bad manners to push food onto your fork or spoon with your knife. Knives are for cutting and that seems to be their sole purpose. The aforementioned (and ever-present) bread - in bite-size pieces, mind you! - must be used for the task.
* In France, one does not take a drink of any sort with their soup (first course). This seems to be very wrong. In some cases, glasses are not even put on the table until the soup has been cleared away.
* And when it comes to restaurants, do not tip your waiter (should you happen to be in restaurant in France, that is). The tip is factored into the total before you're billed and an additional tip is not expected.
It's incredible how much can differ between two "first world," western countries!!