I have eaten at Emeril's and enjoyed it very much. Our dinner was delicious. However, we prefer Emeril's Tchoup Chop in the Royal Pacific Resort. We like the atmosphere at Tchoup Chop better than Emeril's. At Emeril's we were seated upstairs in a rather plain room. It didn't really have the feel of any place special. Now, the service was excellent and the food was fabulous, but I just didn't care for the room we were in. If you do eat at Emeril's, be sure to sit downstairs - more ambiance there.
Yes, you will need a reservation in advance, especially for dinner. If you are planning to go for lunch, you may need less time.
You will also need reservations at Tchoup Chop, if you decide to go there.
Either way, you will have a great meal.
Enjoy!