Once again, do a search on the TripAdvisor website.

As for rooms, depending on what type of room you get at the HHV, it'll be standard to the ones at the Marriott.

HHV is on the North end of Waikiki and includes about four different hotel buildings. Benihana is located on site, which might be a nice place to visit with your four year old (to be entertained) as well as many other restaurants (high priced). A man-made lagoon rests on the property and the beginning of Waikiki Beach to just Makai (oceanside) of the lagoon.

The Marriott is right across from the "prime" spot of Waikiki near the Duke Kahanamoku statue (the one featured in the end of "Lilo and Stitch" -- the one the family takes a picture on). This part of the beach tends to be a lot more crowded than the HHV side, but the quality of sand IMHO is a lot nicer. The Marriott has a few restaurants and is a complex of two buildings connected together by a main lobby. The quality of rooms of the Marriott are standard -- see the TripAdvisor links at the bottom of the page.

My personal suggestion is to go with the HHV. It's a large property and a very lush and attractive place to be (for the most part). The Marriott is simply a hotel and although there is some degree of "lushness," it lacks the atmosphere of the HHV. The HHV is a little disconnected from the main part of Waikiki, however, since it is about a mile away from the "strip," whereas the Marriott is on the end of Kalakaua Avenue where most of the hotels are. Staying at the HHV, therefore (and as noted above) gets you a slightly less crowded beach, but you'll need to drive or take a trolley to get to the stores, etc.

Here are the TripAdvisor websites:
Hilton Hawaiian Village: http://www.tripadvisor.com/Hotel_Rev...hu_Hawaii.html

Marriott Waikiki Beach Resort: http://www.tripadvisor.com/Hotel_Rev...hu_Hawaii.html

ALOHA and I hope you enjoy your trip to the islands...