If you're going to eat out for Thanksgiving, it pays to reserve an
event space for your family and friends. Showing up at a restaurant, event hall, or gastropub on a major holiday and expecting to be seated and served is not a good idea. The staff will be taxed as it is. It's far better to book a table weeks, or even months in advance.
Instead of dining in a general seating area, why not book a private room or banquet hall instead? You'll have dedicated staff to assist with setting up and ensuring the drinks remain topped off. Private rooms are beautifully decorated, with more comfortable seating, and the only conversations happening within earshot are those of your guests.
Private dinner spaces can be inside of restaurants, atop skyscrapers in rooftop lounges, and in hotel banquet halls…Or you can even book the entire dining room of a smaller restaurant, depending on the size of your party. If the venue is a food service one, your best option for dinner is to have the restaurant provide a catered meal. But you can always choose a separate catering service if you're booking an event hall or other flexible space.