touchpad works intermittently

Hi,
I just got my laptop about a week and a half ago and I love the scrolling
function using the side of the touchpad, but I find it works intermittently.
Sometimes it works and sometimes it doesn't. I find whenever I go to the
help function in windows vista and start searching for a a help topic about
it, it starts to work again - usually it stops working while I'm on the
internet watching shows online. Why is this and how do I fix it?
Stacey