Go to Start > Run and type "regedit" without the quotes.
Then find "HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer" by navigating through the folders on the left. Then if you see on the right a key named "NoControlPanel = 1" or "NoControlPanel" double click on it. An edit window will appear. Where it says 1, change to 0 and hit OK.
You should now be able to get back into the control panel. You may first need to reboot before you can access the control panel. Also if the virus/spyware is still active on your system it may undo the changes you made. Follow the 5 steps as mentioned above to get help removing any spyware/viruses.