virus - Windows 7 shuts down automatically on delete key press

1. Whenever i press delete button for deleting files or folder, windows
   7 forcly shuts down the system , i m not sure is this virus or any
   keyboard shortcut malware.


2. on pess key of special char ,its add some extra char also like on
   '' it writes ')'


3. This is making me irritate since i cannot create doc properly nor
   delete any files.


4. I have Quick heal pro and hv malware byte software, after all scanning too
   this virus doesnt stop

Any suggestions are welcome