Everything in and around Ko Olina, where Aulani is located, will be geared towards tourists, especially in pricing. Monkeypod across the street is great with a good happy hour and unique offerings, Roy's is nice for finer dining, and there's a few recommendations at the Four Seasons and Marriott that others can speak to. We had Pizza Corner across the street for a quick dinner on arrival day and it was ok.
At Aulani, Makahiki and Ama Ama were great, though it would depend on if Ama Ama has re-opened and how limited the offerings may be at Makahiki.
If you're touring the island, Kono's in Haleiwa in the North Shore was an awesome quick service stop for lunch, followed by Matsumoto's shave ice close by. People also love the shrimp trucks in that area. Haleiwa Beach House is a nicer sit down in that area.
In Waikiki, House Without a Key (if its open) is often recommended. Duke's is a fun, albeit touristy, spot.
If you can make reservations, I'd suggest it. We live in Buffalo - hardly a tourist area and with fewer restrictions than Hawaii right now - and many of our popular local restaurants are now reservation only solely for crowd management.
