Aloha! You will love WKORV. We will be arriving on 1/15 for 2 weeks.
Our favorite restaurant is Kimo's in Lahaina. A suggestion for breakfast Castaway Cafe at the Maui Ka'anapali Villas (just South of WKORV via the beachwalk/sidewalk). Another favorite of ours for breakfast and dinner is a small cafe called Java Jazz in the shopping center across Honokawai Highway from the Ka'anapali Beach Resort (just North of WKORV via the beachwalk and through the parking lot). Heads up on the wierd bohemian art - a bird cage full of Barbies in the buff, odd paintings, etc. Don't let that scare you off. Good coffee, good food and good music. Another favorite for breakfast is Moose McGillicuddy's in Lahaina.
If you like theater, you will love the production of Ulalena. It is a music, dance and narration production of the creation and culture of Maui. I am not 100% sure, but I think it is from the same production company who does Cirque du Soleil. It is expensive, but well worth it.
If you are interested in a luau, the Old Lahaina Luau does a nice job with their dinner and show. It may be worthwhile to make your advance reservation now, or check with the concierge at the resort. It sells out, so it is worth it to plan ahead if you want to go.
If you have a car, drive up to Haleakala to see the crater. If you go, make sure you take your winter coat. It gets really cold and windy up there. Go in the morning, then stop on the way back at the Kula Lodge for breakfast.
Watch the whales. They are AMAZING and it is free! You can see them from the beach and maybe from your lanai. Take binoculars if you have them.
Use the resort shuttle to go to the Whaler's Village and Lahaina. It is free and more convenient than trying to find parking in Lahaina. We don't even rent a car. We use Maui Executive Shuttle to go from the airport to the resort and back. It is about $50 each way from the Kahului airport for 2 passengers.
Have fun!