How do you progress through the Droid Explorer unpack option?
This looks like (as stated in my comment above) that it has to do with the Path of Java not existing in the windows PATH environment variable. 

I am adding your comment as well as part of this answer:


  Weird, that was (sort of) it! Java was in fact in my PATH environment variable, but it was using the directory C:\ProgramData\Oracle\Java\javapath\ which contains only 3 symlinks to my actual Java bin folder. Double clicking on any of the symlink shortcuts results in the window I noted above. I temporarily changed my PATH variable to point to the real Java folder, and then your Unpack feature worked fine. (I then put my PATH variable back, since I don't know what potential security issues I'd open myself up to by leaving it altered.)