Jinglebells, JB is fab for toddlers. When we booked we were under the impression that the kids club was over 3 years only. A good friend of mine went there literally a few weeks before me and kids club (Sinbads club I think it was called) was closed for refurbishment and it just re-opened when we got there and was fabulous. It has a little outdoor pool area which is fenced in and they take the kids out for supervised splashing etc. We could put DD and DS in for either a 4 hour (FREE!) session in the morning, 3 hours in the afternoon or 2 hours in the evening (dinner time).
Actually, I suspect we will end up going there again instead of Atlantis!
It is not cheap, but it is fabulous and what price do you put on a few hours of relaxation knowing that your kids are safe. Also, they staff in the kids club do babysitting in the evening in your room (at an additional charge)
Breakfast was I think around 25 pounds each for DH and myself (stuff yourself stupid buffet from around 7am to 11am) but think kids were free. Lots of options for lunch and dinner from cheap(er) restaurants/bars to a very expensive and yummy argentinian steak restaurant.