I don't get to stay at the POly until next year (can't wait), but I have stayed at the Tower in CR, with a 2 year old. I really enjoyed it. Chef Mickey's is right there, which was great for us. My son also loved watching the monorail come right through the building. I liked the ease and convenience of everything being right there. Also, you share busses to MGM with Poly and GF. The good thing about the CR is that you are first on the bus to the parks, meaning you get a seat, and first off back to the hotels, so if you are standing, it won't be for long.
The pool was nice, but it was a hike out there from the tower. Also, it is not zero entry, so we had to hold the little guy whenever he was in the pool. They do have life jackets though and every day but one, the lifeguards let my little dare devil down the slide. I would definitely stay there again, but we wanted to try the poly.
Budly