In short: no. The first problem is access to the filesystem, which in most browsers is set to no by default due to security reasons. Modern browsers sometimes support minimalistic storage in the form of a database, or you can ask the user to enable file access.
If you have access to the filesystem then saving as HTML is not that hard (see the file object in the JS documentation) - but PDF is not so easy. PDF is a quite advanced file-format that really is ill suited for Javascript. It requires you to write information in datatypes not directly supported by Javascript, such as words and quads. You also need to pre-define a dictionary lookup system that must be saved to the file. Im sure someone could make it work, but the effort and time involved would be better spent learning C++ or Delphi.
HTML export however should be possible if the user gives you non restricted access