You can't visit Lahaina without seeing Ulalena at the Maui Theatre. It is a well done, and entertaining production. Staff is friendly, accommodating and happy to see you. Performers are professional, and production is well done. Keep in mind that this is not Las Vegas or Broadway, but a well done, and entertaining local production.
Get the Dinner Package which is a fantastic value, and you will have your choice of eating at Lahaina Prime Rib and Fish (my choice) or Ruth Chris (if you want to stick with a well known brand that you probably already know). You also get VIP seating for the show (there is not a bad seat in the house, but this puts you close up).
Support the Theatre, support the performers, and have a great night out in Lahaina!