If you are putting Windows 7 on the computer, than make sure you download the Windows 7 drivers
for your laptop and have them handy offline, such as on a flash drive, so you can easily reinstall them once Windows 7 is installed. You definitely want your network drivers, so at least you could get the laptop online and let Windows Update find the rest.
Since you have an OEM system, you should be able to get them all from HP's website by putting in your model number. If HP's site doesn't have Windows 7 x64 drivers for you, then you'll probably have to get them from each manufacturer's site, like Intel, etc. That's an easy process, but this is why it is important to know the specs of your laptop.