Agreed, unless you have an AP, don't use up a day's admission just to eat if you weren't already planning on going into a park anyway and you need the day for another time.
If you have an AP or a day's admission you want to use for that night you could always head into World Showcase. Lot's of really good options, including Le Cellier and Chefs de France, among others. Plus you'd get to enjoy World Showcase for the evening, explore the countries, take in some entertainment.......and see Illuminations, nice way to start the vacation. On our last trip we arrived at the BC for check in around noon. Relaxed around the hotel for much of the afternoon, hit the pool, then headed over to Epcot in the early evening. It was nice......but easy for us to do since we have Annual Passes.
If you don't want to use an admission day that evening you have a couple of options.
You have a lot of nice places right at the hotel. Beaches and Cream is a fun place for burgers and sundaes. As you mentioned, you could go to the Yacht Club. As others have mentioned, there are good options on the Boardwalk, or at the Swan/Dolphin. If you aren't going into Epcot keep in mind that you can see a lot of the Illumonations fireworks from the bridge that leads over the canal to the Boardwalk. The fireworks are at 9:00 and you should catch some of that.
Another nice option would be to head over to a MK resort for dinner. One night on our last trip we had dinner at the GF (the dinner buffet at 1900 Park Fare is great) and caught the MK fireworks from the deck/dock at the GF. They pipe the music in and it's another nice way to start the vacation without using admission. You might even catch the Electrical Water Pageant. There are lots of other nice options at the monorail resorts as well. Of course to do any of this you'd have to get yourself over there. Without a car it might not be worth the effort, although you could take a bus from the BC to the MK and then enjoy the monorail ride to whichever resort you pick for dinner. The GF is a beautiful resort to see if you've never seen it.