keyboard messed up

Alright, well i had a computer with windows 98 and then
installed windows xp on it. i recently restored my
computer, and installed windows xp again. the problem is,
my keyboard isnt working properly. i have one of those
keyboards with the shortcut and volume buttons on it. and
well they don't work. the same thing happened last time i
installed windows xp, and i had to go to the microsoft
website and download a driver or something like that
because i needed it so that my keyboard can work properly
with xp, except i forgot what i downloaded or where i
went to download it. what do i do? please somebody
help!!! write back to me to my email address please!