Wanderlust,
Which part of Canada are you from? A few thoughts and questions.....
My suggestion would be to visit your nearest travel agent, as they can put a package together for you that includes flights, transfers, hotels and tours. That might save you some money. If I remember correctly from my visit, the agent arranged a presentation with tour companies the day after arrival, and I picked the tours I was interested in. You might get some good ideas on tours by having a look at this website - https://www.robertshawaii.com/ . I believe Roberts also provides an airport shuttle.
Are you interested in the Pearl Harbour history? If so, plan to spend the better part of a full day on that, as there are four main sites to visit (USS Bowfin & Submarine Museum, Arizona memorial, USS Missouri and the Pacific Aviation Museum).
After seeing the traffic in Oahu, there's no way I would recommend driving there. I let the tour company do the driving, as it provided a much more enjoyable visit. One of the tours I took was the Grand Circle Island tour and it was so much easier to have someone else driving so that I could enjoy the scenery and take pictures. Car rentals can be expensive in Hawaii, and of course fuel is not cheap (currently US$ 2.89 - 3.09 per gallon on Oahu or ~Cdn$4.10, according to Gas Buddy).
One additional point to mention is that many hotels in Hawaii (and elsewhere) charge "Resort Fees" (they use a variety of names to describe these). These are in the range of US$ 25 - 50 per day, are usually compulsory even if you don't use the services they cover, and these may not be shown in the hotel room rates. You may find this website helpful - https://www.tripsavvy.com/additional-taxes-fees-when-traveling-to-hawaii-1533988 (there's a link on that website under "Resort Fees" that explains some of the other charges you may get nicked with).
Good luck with your planning!