yes the cruise is on a pontoon boat. I would say doing the birthday cruise as a surprise would be a great idea. But don't delay - the cruises sell out quickly. This could be a busy weekend with Mother's day crowds. We have taken the Illumination's cruise (w/o cake) and it is an awesome experience. We have given the cruise as an anniversary gift with cake and beverages and it was a hit! If you are wanting family time, this would be special. If you can't get a cruise, and you want to include the kids, a character dinner/breakfast would be fun. Not only would your wife have a good time, but as you said, she would love watching your daughter enjoy herself. You can also call ahead to most of the restaurants and arrange for a birthday cake. Have a wonderful time as a family!