We ate at Mina's Fish House this past June. We made our reservation on OpenTable when we arrived at Aulani. The restaurant was booked during the early evening times so I would recommend making a reservation early on. It was a very quick walk from the Aulani lagoon entrance to Mina's.
My family (3 adults, 3 teens) enjoyed our dinner out on the large table facing the lagoon. It was a beautiful and cozy atmosphere with the string lights, fire torches and fire pits around the table.
The food was very good. Everything on the menu sounded delicious. We ordered a couple of drinks, several appetizers, a salad and soup, several fish entrees and a surf & turf. Plus my daughter ordered from the kid's menu since she didn't see anything she liked from the main menu. Our dinner was a little over $550.
On a side note, I've heard wonderful things about the La Hiki's Sunday buffet brunch at the Four Seasons. We were leaving for home on Sunday late morning, so we couldn't go. We're definitely going to try it out the next time we go to Aulani.