I've had both and I'd say put some time in on them if you are able before you make a decision. There is a lot more going in in POTC (Sinking ship, Spinning Compas, Treasure Chest, Jack the monkey), the ball times are longer which is great for the family(no one likes to drain all the time). Alot of fun for all skill levels
IronMan can be a blast as well, but very frustrating, very short ball times and a little plain compared to Pirates. I would recommend getting the large out lane star posts if you go IronMan. If it were me, POTC all the way considering family