We have eaten at Cape May for our Thanksgiving dinner twice now and it was exellent both times. Both years about half the buffet was traditional Thanksgiving items, and the other half salads and seafood. Their desserts were to die for, and there were so many different ones to try. The first time we had a party of 15, and everyone really enjoyed their Thanksgiving dinner. Two years later we were in WDW for Thanksgiving again and staying at BC for that trip. When it came time to book Tday dinner it was a no brainer, Cape May had been so enjoyable the first time that we booked it again, and it did not disappoint. After dinner you should take time to walk the lake and check out all the decorations at the resorts. We toured BC, YC, BW, Swan and Dolphin. It was a very nice evening and is sure to put anyone in the Christmas spirit.
Just to be fair, we've also dined at Yatchsman's and had a fantastic meal. We actually ate at Yatchsman's on the same trip as our Cape May Thanksgiving dinner. While Yatchsman's was absolutely incredible we felt for a family Tday meal Cape May was the better choice, and a lot cheaper. DH and I did Yatchsman's as a date night so only had to foot the bill for 2 adults. Good luck with your decision.