Hallo Thorsummoner, I looked up your friends specs ; Product Specifications Compaq Presario SR1320NX Desktop PC - HP Customer Care (United States - English)
I see HP havnt released new drivers
for it since XP, if the Hardware is stock as you say the two things that stand out for me is you will have to upgrade the ram to at least 1GB you can go up to 2 GB.
Also you may need to upgrade the Graphics card as it only has 64mb dedicated graphics memory which may work if you dont use Aero but you really need at least 128mb dedicated graphics memory
If you need advice on a Graphics card i would suggest posting in that section of our forums.
You may find this tutorial guide helpfull for sourceing out drivers; Installing and updating drivers in 7
I only hope this is of some help in getting started
Edit; you may also find this of help; Windows 7 Upgrade Advisor
=Installation and Setup