Waikiki is a city. The Hyatt is nice but not a luxury resort from what I remember. Not sure what you want to do but it would make more sense to choose your island and then your hotel. Few poeple come to Hawaii and spend most of their time at a hotel ... There's so much to see.
The Fairmont in Maui is not isolated but it is much quieter than Waikiki. It's an all suite hotel and on a great beach in an upscale resorts area (but at the end of the main area so less crowded.) You will most likely want a car.
Please tell us 1) where are you from? 2) will you have a car? 3) when are you traveling? 4) how many nights will you be in Hawaii? Please add your hometown to your profile.
Choose your Island first ... then focus on the accommodations. Absolutely.
The Hyatt Regency on Waikiki is a very nice hotel (not a resort - it is only a huge building - no grounds). Great views. Excellent location, but that area is very crowded (and walkable!). Small pool on 3rd floor. Wonderful beach across the street.
If you want plenty to things to see and do in a more concentrated area - you do want Waikiki/Honolulu. Take a look at the Royal Hawaiian Hotel.
Again, choose your Island first - and then your accommodations. Have a rough budget in mind. Access to a car makes a huge difference.
Do you have a map of Maui? Oahu? You need them before trying to decide accommodations.Edited: 14 January 2018, 05:01
(Welcome back, BLBL--still trouble with your TA accounts?)
I agree you need to pick the island first. How did you end up choosing these two hotels? What do you want to see and do in Hawaii? When will you visit, and for how long?
I highly recommend you decide which island you would like to go to then pick your accommodations. Both islands are wonderful but very different.
Maui is much more laid back.
Both hotels are worth staying in!!