that laptop is fine for CSS, you should be able to run that game at 40 fps easily.
make sure your resolution isn't sky high, 1024x768 is the most you will really need.
make sure your graphics card settings aren't forcing some settings before the game settings (like mentioned above anti aliasing is a big thing)
turn off v-sync
if your card supports scaling, set it to less intensive mode or turn it off completely
switch smoke animations to simple (google this one, it's a console switch in game or options menu, can't remember)
last case if all else fails to help, look for casey's mod (might be spelled differently) basically it's a cal legal mod that reduces the number of visual candy you see in the game (dead enemy bodies, blood splatter on walls, bullet holes, sprays, etc) it should be able to decrease the load by a decent amount and get you another 10 fps or so.
all i have to say, your machine is very capable of running CSS, you just have to get the settings right. my GeForce Go 7400M was giving me 50 fps easily most of the time