It would help to know price range, type of food, etc. that you are looking for.
Without knowing all of that I would say anything but Victoria and Alberts would be appropriate. All WDW restaraunts are very kid friendly but since it is a birthday I would reccomend a signature restaraunt.
As an example, I am celebrating my birthday this weekend at California Grill with my daughter and two nieces - they are all under the age of 8.