It sounds like there may be some restrictions on the the file you have. In other PDF files, can you do the highlights and sticky notes?
You may want to try a third party PDF reader too like Sumatra or Foxit and see if you can use the highlighting tools in those programs and what happens if you then open them back up in Adobe Reader.
Also another workaround, by default you have the XPS printer installed in windows 7. You can print the document to XPS then using something like cutepdf printer (Foxit PDF comes with a virtual pritner as well) print the XPS document back to PDF. i.e. print PDF->XPS then print XPS->PDF.