The Flying Fish has fantastic scallops and the best mussels appetizer that I've ever had on property. On the DxDDP I was allowed to get a virgin strawberry daqueri as my beverage there. As a solo I sat at the bar and had the best time with the people around me and the great waiter I had. The only thing I didn't appreciate is that I was too full for my dessert, so asked for it to go. They charged me a to go fee, which no other restaurant in WDW has ever done.

There were quite a few kids there that night, but they were all well behaved and seemed to be having a good time.
Spoodles I've tried twice and am still not impressed with it. I had a bad table and really bad service every time. The last time the waiter brought me the wrong dessert then argued that that was what I had ordered and walked off. Neither time could I get my water refilled. The first time I ordered a glass of sangria and never got it. The food I did get was really good though.
Grand Floridian I've only eaten lunch at, but it was very good. Quiet, peacefull, and received excellent service. Loved it!
Narcoosee is one of our favorite restaurant. If you don't like lobster, you can order the Surf and Turf with scallops instead. You will get a full serving of scallops, plus the filet medallions. Both are sooo good. Their calamari is also very good as is the cheese plate. Narcoosee has the absolute best dessert on property though with their almond cheesecake. You had better like almond though. It is soooo good, I'd go there just for that cheesecake. Plus you can see the fireworks and the electrical water pageant from their deck, if you time your ADR right.
Of the four restaurants you asked about, the only one I wouldn't return to is Spoodles. Some people love it, but I gave it two chances and both times got horriible service there.
Well behaved kids are welcome at any WDW restaurant, except Victoria and Alberts and Bistro de Paris.