Hi Laurie,
Some of my favorite restaurants are somewhat near the Eiffel Tower in the 7th. A caveat with these places--they aren't "touristy" in that they cater to tourists, but the 7th is a neighborhood that attracts a lot of foodies, so you are definitely going to see tourists here. I'm a little unsure about the combo of the "celebrating" request, and I'm assuming that you'll have kids because of the "family" mention...
Cafe Constant is a wonderful little cafe run by a Michelin starred chef. Go early or late--it will be packed at 7:30. I've seen lots of neighborhood families here, especially for weekend lunch, but it's a cafe so I'm not sure it's a celebration type place. One of the chef's Michelin starred restaurants is just a few doors down--Le Violin D'Ingres (reservations required). I consider it midrange--menus are 49E/pp. It was the best meal of our recent trip. I wouldn't normally think of it as a family place--men will need to wear a jacket, as they would at any nice restaurant in Paris--but on my last visit, there was indeed a large family group with young children, and the staff was very accomodating. (French kids of course don't survive on chicken fingers like American kids, though).
Info for both, here:
http://www.leviolondingres.com/eng_ambiance.htm
(The same chef also has a Michelin starred seafood place that is excellent--Fables de la Fontaine--but I've never seen kids there and am not sure they'd be appropriate)
Chez L'Ami Jean is a longtime neighborhood classic (since 1927), and it attracts a lot of foodie tourists as well as locals. It has a very cramped and casual but festive feeling. It's Basque and traditional French so don't go with vegetarians (very meaty, a fair amount of offal, menus I think 34E). La Fontaine de Mars also comes to mind, though I think it's a bit pricey for what it is. Traditional French, another local and foodie favorite.
Definitely also look at the Michelin guide online that Kent links.
