Use a boot to the Last Known Good Configuration. More reading about System Restore at http://reviews.cnet.com/5208-6142-0.html?forumID=5&threadID=34243&messageID=395242&tag=
In parting, I have yet to need a "keyboard driver" beyond what Microsoft installed. Your post does not tell why or what effect you were attempting to achieve.
In trying to set up an external keyboard I changed the driver details of the inbuilt keyboard and now it wont work. I get the error A driver (service) for this device has been disabled. An alternate driver may be providing this functionality. (Code 32)
any ideas how to sort this out please