Well, this laptop comes with a good processor, and lots of RAM, now, Need for Speed Most Wanted is not one of the latest games, and it's not going to stress that much your PC, what I normally do, is putting everything maxed out, and you'll see if the game runs smoothly.
First of all, download the latest drivers for your graphics card, from the ATI website, then open up the Catalyst, and I think you should leave the 3D options to balanced, besides, if you need more quality, you're going to change it inside the game, not from the catalyst itself.
Then, run the game and go to settings, try to use everything on maximum, I think your PC can handle THAT GAME very well, and if you feel the game a little bit laggy, start decreasing settings, just like anti-aliasing, and the details levels.
If you're afraid that something could happened to your laptop because overheating or something like that, what you can do is play like 5 min of the game, then pause it and press windows key, go to your desktop and open up your ATI Catalyst, and on ATI Overdrive tab, you'll find the temperture of you video card.
Also, if you want to know some other temps of your PC, you can download this programs:
You can set some of those programs to play a sound or send you a pop-up window telling you that the processor temp or the graphics card temp is going too high.
PD: Also, if you want, you can buy a laptop fan, so it'll cool your PC even more.