|If you don't have a restore partition you can boot to then first check to see if you can order the disks from HP:|
If not you may be able to order them from a third party. Google something like "cq71" restore disks order. What you're looking for are the complete restore disks and not just a 'driver recovery'.
You can also do a fresh install using a generic windows vista disk and the product key on the bottom of your laptop. Or there are probably download sites for a vista ISO that you'd burn to a cd or dvd (whichever is appropriate--I'm not sure what vista comes one) and again using your product key.