Is your 2 year old toilet trained? The only place you can wear swim diapers on the magic is in the Nephew's Splash Zone. We sailed on the magic when my youngest DS was 1.5 years and then again when he was 2.5 years. Nephew's Splash Zone is pretty small, just a bunch of fountains squirting up from the floor. It's in a glass enclosed area with a door. DS brought his sand bucket up there and had fun filling the bucket with water and then dumping it out, but that's about it. It held his attention for about 25 minutes, and DH and I were bored out of our minds. Because it's in an enclosed glass area, there's nowhere to sit and relax while they play.
He couldn't play in the Aqua Lab because you couldn't wear swim diapers there, but Aqua Lab is actually too much water squirting everywhere for a toddler anyway (at least for mine).
I had to distract him because he really wanted to go in the pool with his big brother.