Fn key??
http://en.wikipedia.org/wiki/Fn_key


if you can give your laptop specifics I can look for more detailed information for you.
brand , make , windows XP or vista, Mac or Linux etc??
how old is it?

if you have a spare keyboard {or a friend does} you can plug it in to use until you get it figured out.

or can you get to your control panel settings?
there should be something for keyboard settings

does the touch pad still work OK?