We went recently to the Shangri-law in Cebu (Philippines) and our ten month old loved it!
The beach is small, but very nice....and the sea is not only crystal clear but full of fish that come right up to to your ankles. The hotel supplies bread for you to feed the fish with and they eat it right out of your hand. My son was fascinated by the fish but completely disgusted wih the fact that I was throwing the bread into the sea and not into his mouth!
They also have a great shady place on the beach with lots of beach toys for little ones to play in when it gets too hot.
There is a kids club where you could take him to play inside, and they have parties for kids everynight!
The gardens are beautiful, and the staff fantastic!
The pool is also great.
And my ten month old loved the buffet breakfast!
There isn't much else to do in Cebu though apart from being in the hotel, on the beach etc. The hotel has lots of water sports though if that's your thing.
Other options include- Phuket, Singapore, Malaysia....