I've compared your stats to the required specifications. Altough there is no specific processor speed youir laptop needs to use the PVR, the site does mention that a fast CPU is very recommended. You run at 2Ghz, which is not that slow for a laptop.
What's worse, if you check this link;
You must login or register to view this content., and look at "possible processor combinations" with your 915pm Chipset, you'll see that the fastest processor for your laptop is the M-780 which offers 2,26 Ghz of speed.
Seeing how you currently have a M-760 with a processor speed of 2 Ghz, the increase in speed by switching these processors would be insignificant; in other words, how the PVR performs on your current laptop, will most likely determine how it will perform with the new processor as their speeds are about the same.
Should your laptop not be able to keep up with the PVR-recording, the only viable option is to buy another laptop, because you can't change the Chipset which limits you current possibilities to a tiny increase of 260 Mhz.
But,
That doesn't mean the PVR won't work on your current laptop though . 2ghz and 1GB RAM could be sufficiënt. What makes you say your system is not fast enough for it to work?
I can't see anything that you don't have besides service pack 3, but you can download that for free from mircosoft.