If you want peace and serenity, book Pullman Phuket Arcadia Naithon beach (10 mins from airport). Book an OCEAN room. I repeat, ocean room. Don't bother about the other categories unless its a Villa.Then email the hotel and strongly request for Block 3. When strongly requesting, try to say you are celebrating something or state that a friend of yours has stayed there and recommended it to you. Reason being, block 3 are the hardest rooms to get as it offers the best views of the ocean and many people also request it. So best is to say you are celebrating something or say your friend recommended it strongly.
If you want hustle and bustle, Patong beach in other words, book the Grand Mercure or Novotel Phuket resort. Note that the Grand Mercure is not along the beach but just a 5 min walk from the beach. Novotel is located at one end of the beach on a slight hill. Views from the hotel is not bad too.