This was a great trip through history. All was well done and very respectful of those who sacrificed their lives. My group got there early (for the free tickets - they only give out 1,000 per day, first come first served) and paid the extra $7 for the audio tour (by Jamie Lee Curtis! Ha!). There is a small museum on site and then you take the boat over to the Arizona memorial. The whole thing probably takes an hour.
If you’re just an average tourist I would NOT pay for an actual tour guide, like a few sites are offering. It seems unnecessary. I’m sure they give you a lot more info, but with the $7 audio headset rental I felt like I fully understood the surroundings.