Keyboard & touchpad locked out on Vista laptop

Please don't respond unless you totally read and understand my problem.
1. HP Pavillion dv9207us (RP282UA#ABA) [laptop]
2. Windows Vista Home Premium edition
3. Keyboard and touchpad have stopped working, but Bluetooth mouse works.
4. 'Software' keyboard pops up on screen to use with mouse, but NO hardware
keys respond and the touchpad is also dead.
5. When attempting to reinstall [or connect an external keyboard] I received
the following message:
----------------------------------------------------------------
Windows found driver software for your device but encountered an error while
attempting to install it.
Standard 101/102-Key or Microsoft Natural PS/2 Keyboard
This operation requires an interactive window station.
--------------------------------------------------------------
6. The "Keyboards" section of the Device Manager is showing two "Unknown
devices" with yellow triangles with exclamation marks and I am unable to
locate the keyboard and touchpad drivers using the Recovery Manager.
7. Uninstalling the drivers in Device Manager only starts Step 5 all over
again.
8. I do not have restore point before the problem came about and do not have
the Windows Vista Installation disk since the computer was shipped with only
the Recovery partition on Drive D:\ which is inaccessable. [See Step 6
regarding Recovery Manager.]
9. THE KEYBOARD DOES WORK AT THE BIOS LEVEL. IT JUST STOPS WORKING WHEN
WINDOWS VISTA BOOTS.
10. Problem started after removing a game [installed from HP website].
Q.1: What is the "interactive window station" Vista requires for the driver
installation?
Q.2: Is there a simple, stupid thing that I have overlooked? Remember this
is a 2007 model HP laptop.