Both words can be used in different situations, but there is one case when their meaning is quite similar, e.g.: Мама: помой полы, пожалуйста! Сын: хорошо, помою. Сын: ладно, помою. I believe, there is small emotional difference here. "Ладно" is more about doing a favor, while "хорошо" is just a confirmation, like "yes, I will do it, no problem". But it could be my personal perception. Others please correct me!

ладно - с оттенком одолжения или уступки собеседнику хорошо - ОК