Although it won't make a huge difference in performance, I've seen the correct driver cause the Windows Performance rating to jump a whole point, or so.
Visit the nVidia site and see if they have something newer than the one that came on the CD.
Still, laptops really aren't the ideal tool for playing games.. Desktops have better choices for upgrading hardware for gaming.
Hope this helps.
I have the NVIDIA GeForce 9600M GT card (laptop) in a Qosmio laptop from Toshiba.