Activity Links nearby: 

Waikiki Beach Less than 200 yards to the famous Duke Statue on Waikiki's premiere surf-beach

Surfing, Windsurfing, Snorkeling & Diving, Boating, Sailing, Parasailing Many rental opportunities within 500 feet.

Hiking So many options, too many to mention. Beach, ridge and valley hikes (often end at a stunning waterfall)

Biking: Bikes can be rented at many nearby locations.

Golf: Many golf courses on the Island. The nearest is just about half a mile away.

Tennis: Many courts within walking distance. The nicest court (in Kapiolani Park, surrounded by Palm trees and Hibiscus hedges), at Queen's Surf beach is about 5 minutes walking distance.

Basketball and Beach volleyball is played almost daily.

Fitness Center: 24 Hours Fitness is on the corner of the next block, with stunning views of the beach and palm trees while you work-out.

Fishing

Shopping

Cinemas, Museums

Honolulu Zoo and Waikiki Aquarium

Diamond Head Crater a lovely short hike. On the first morning you will be up early anyway. Sunrise at Diamond Head Crater is a wonderful and romantic way to start the day.

These links are a quick start for your own research and are not meant to be a recommendation.