Going to Thailand in April, should we go to Phuket, Ko Samui or Hua Hin?

We are going primarily for vacation and relaxing, hoping to do a few excursions. Ive read a lot about the weather being different on each side and dont want to mess us and ruin our trip booking in the wrong place. Also, I would love to stay where (or near) where Bridget Jones did ;) Does anyone know where that is??