All of the restaurants on Disney's Dining Plan can be very crowded and noisy. I would recommend one of the restaurants not on the plan. Bistro de Paris at Epcot would be my first choice. Not only is it not on the
DDP, they do not have a children's menu, do not do special accommodations for children, so this is generally a pretty quiet restaurant. We enjoy Bistro almost as much as V&A. Others would be bluezoo, Il Mulino and Shula's; these are all located at the Swan/Dolphin. As long as there is no big convention going on at those hotels, these places are generally quieter also.
If you are set on one of the restaurants on the Dining Plan, Artist Point is generally the quietest of all the signatures. Jiko and Citricos are usually quiet but not always.
You could also check into Private Dining at the Grand Floridian. You have the Citricos menu but you are placed on a private patio area. My son did this earlier this year for his proposal dinner and said it was great.