Hi Kimberley!
No matter what time you arrive at Walt Disney World, its a great time to start enjoying your vacation! And a great meal is an excellent way to do that!
If you'd like to relax a bit at your resort, I can highly recommend dinner at the Polynesian itself at (my favorite)
Kona Cafe or at the crowd-pleaser:
O'hanas. This would give you time to relax at your resort, enjoy the pool and have a great dinner. After dinner, you can head to the Polynesian's beach (or pool) to watch the Electrical Water Pageant or Wishes!
If you'd like to head over to the Magic Kingdom, one of my favorite places for a table service restaurant is the
Crystal Palace. Nothing can start a vacation off right like dinner with Pooh & friends! If you'd like to play it more by ear, and go for a quick service dinner, Columbia Harbor House is a great choice!
Hope this helps! Have a great vacation!