[Lostbrain]

The Harry Potter stuff at Universal is fantastic, the Hogwarts Express is so beautifully done I'd definitely recommend a park hopper ticket, but if you can only do one do Diagon Alley, the details in the area are just amazing. Your toddler would need help but would probably enjoy the interactive wand stations, our kids had a wand to share and although I thought it expensive, I'm glad we did.

As mentioned the Dr Suess bit is really good, my 10 year old liked it! There's lots happening as you just wander around all of the parks, we have one thrill seeker and another who gets motion sickness and she was quite happy hanging out while he was on rides.