|I agree that your system may be slow to begin with and maybe ram may help.|
Usually the score is the score and no amount can change it. Only the worst part is the 3 and other parts may be higher.
Before I'd waste any money on it, I'd look for a new system. Might be worth it as you get windows 7 (or 8 if you are crazy) and a warranty and even lower models may rate a 4 or 5 out of the box.
If you really need it to speed up, you may have to reload the OS from OEM media.
Hang up and live.