Suggest you to Bangkok becuase there are a lot giant shopping malls and great restaurants there. The things are cheap and good. You could do shopping and eating for the whold day in these malls and no need to go out.
Recommend to stay hotels near the MBK Shopping Mall, such as Novotel Siam or Phatunwan (cannot remember the exact spelling, ask the agent they should know.), the mall is near the skytrain as well.