You need to lay down some more parameters. Then we all can help you. Flying is OK with the little one, are long car rides ? Museums ? Temples ? Hikes ? Oh, you're not going for a year & he'll be 2 & 1/2 - better. Don't expect nice even sidewalks in Thailand. In BKK they are broken and very crowded. They're tough enough to walk on, without spraining an ankle, impossible with a stroller. I see you're SPG, so all the Starwood properties should work for you. The Royal Orchid Sheraton has been refurbished recently and is right on the river, near most of BKKs top sites. For Phi Phi you fly to HKT, cab to Phuket Town, and grab a ferry. Maybe fly in to Krabi, stay a couple nites, boat to Phi Phi - 1 nite, & boat to Phuket. Get a hotel there and fly back to BKK from HKT. Kao Lak and Krabi have nice pools, beaches, day care, and baby elephants you can swim with. The Phuket properties should work for you as well. Air Asia and Nok both fly to both Phuket & Krabi inexpensively. I can't say that for Bangkok Air & Koh Samui. It'll cost you about $150 each for that short flight, OW. They built the airport and had exclusive rights until recently. If you want to take the 1st or last flight, you can knock it down to $80 maybe. May I suggest Koh Chang. It's big, beautiful, & somewhat unspoiled. 5 hrs away by car, if you dare rent. You can get a cab or private driver for for $100-150. Minibuses are available from Victory Monument too. $20 each or so. They leave when full. So pick one almost full. My favorite island. Great beaches, mountains, waterfalls, etc. The hotel I stay in is remote & hard to get to. Not recommended for you. The KC Grande in White Sands Beach is nice and they have some special on TAT which looks like 1/2 price. Here's a good website for you: http://iamkohchang.com/