I looked briefly online and saw something about pressing function+F11 when the keyboard was going wonkey and adding numbers to letters and such. No idea what that does, but sometimes laptops have some funny things bound up in the F keys.
Otherwise, I'd try updating or reflashing the BIOS. BIOS is kind of like the basic operating system that is there to enable your computer boot up and load the full blown operating system, and it also handles some hardware stuff, like keyboards.
Make sure you know the whole procedure before getting started and don't let it get interrupted. If you need a bootable CD and can't burn one you might be able to make a bootable ***flash drive (if your computer will let you boot from a USB port)
***When I thought I'd become a computer geek I'd run a small operating system from a flash drive. I couldn't run an operating system from an external USB hard disk drive, however