On my Toshiba laptop there is only one key (for Vista Business). I got XP restore discs with my laptop, so there is no problem at all - and you don't have the discs?
I visited HP's website and looked for your laptop's page. No clear instructions there. I believe that you don't need to contact M$. Take a look at your manual first, and if there are no instructions, take contact to HP. If they can send you discs, it's possible that you should pay about 10 - 30$ for the them. Your model was not listed in HP's Windows 7 Upgrade program's eligible models list.
I visited HP's website and looked for your laptop's page. No clear instructions there. I believe that you don't need to contact M$. Take a look at your manual first, and if there are no instructions, take contact to HP. If they can send you discs, it's possible that you should pay about 10 - 30$ for the them. Your model was not listed in HP's Windows 7 Upgrade program's eligible models list.