|Try a PS2 keyboard and mouse if you have one around or a USB/PS2 adapter. Have the drivers (Windows 7 drivers) ready to install if this or any of the repairs work.|
Try a Start Up Repair from a Windows 7 Repair Disk. If your father did not make one originally, you can make one from another Windows 7 machine as long as both are 32bit or 64bit. You can also run the repair from the install of upgrade DVD that your father used to install the upgrade.
If the keyboard works in the BIOS then it should also work during install from a Windows 7 install of upgrade disk since it will load default drivers when you boot to the DVD. You can probably just do a repair install right over the existing installation, but if you do not need to save anything, I would just recommend a clean install. When you boot to the disk, select Custom and Partition, delete the existing partitions, create and format a new partition and format it. The proceed with the install. An upgrade will 'see' the original install before you begin and allow you to proceed. You will need all of the Windows 7 drivers just after the install (or repair) so download them to a flash drive or CD ahead of time so you will have a faster time of it when you are ready for them.
If Windows 7 drivers are not available for your hardware, Vista drivers will often work, but not always (this is a possible reason for your problems, the Vista drivers may have worked up until a Windows update may have prevented them from working).
You have to be a little bit crazy to keep you from going insane.