If you want to move a project,
you should close the project in NetBeans, move the directory and then open the project in a new location.
However, if your goal is to be able to return to an earlier version, far better option would be to use a version control system. In my opinion these are great for small and hobby projects too. I personally would recommend a distributed version control system, such as git or Mercurial, since these seem the easiest to use in small (one user) environments.