I lived in Oahu 3 years, read my review!!!
I was stationed in Oahu for over 3 years and recently had to come back home to Houston. I loved the place, never a dull day, never an ugly day, even in bad weather I was awed at the beauty of the island. The weather is pretty much year round average in the 80s, and from mid December to mid January it gets really rainy and windy. If you want to hang out at a relaxed and gorgeous beach, white sand, swim in the water, head to Kailua/Lanikai Beach on the Windward Side of the island (East/Northeast). If you want to enjoy the best snorkeling in Hawaii, check out Hanauma Bay, you're blessed to swim with the peaceful giant sea turtles. For the best breakfast in Waikiki, it's the Wailana Coffee House across the corner from the Hilton on Ala Moana Blvd. There's plenty of night life in Waikiki alone, and in Honolulu, just down Ala Moana Blvd, is the mall, the Ward center with theaters, restaurants and a Dave & Busters. If eating in Kailua, try Boots & Kimo's, trust me, ask any local how to get there. If eating breakfast in Kaneohe, without any doubt, hit up Koa House, that has to be the best on the island. I loved the Loco Moco from L & L Drive Inn, trust me, it's good. Please visit Pearl Harbor, i was on the island for 2 years before i finally did, and it was a very sobering experience. Take a trip up to North Shore to check out the hard core surfers in action, the turtles lazying it up on the sand. You'll enjoy the ride up H-2, or the long way on the H-3, through the tunnel, you get an amazing view of the Windward side of the island and all the cliffs. If you like camping, and dont mind grabbing gear at the Sports Authority in Honolulu or at Walmart, spend a night in Waimanalo on the beach, just southeast of Kailua. It gets a little breezy and cool at night, so cozy up, but the clear view of the stars in the Hawaiian night sky is awesome. And be friendly and courteous to our local kama'aina, the residents of Hawaii. Pay it forward, and trust me, you'll have a pleasurable time around them. Word from the unwise, don't act rowdy, obnoxious or arrogant when out dining or at a bar, the locals do not like their relaxed vibe to be disturbed. It's Hawaii, soak it in, relax, don't fret or stress out. Enjoy!