From Suzhou to Tongli or Zhouzhuang

Hello

My family will be staying 2 nights in Suzhou in July. Is it possible to visit Zhouzhuang or Tongli during a day trip? how long time does it take from Suzhou? What is the best way to travel to Zhouzhuang and to Tongli? If we have to choose one city, which one is to prefer, Zhouzhuang or Tongli? Thank you so much!