Need for Speed Most Wanted seems to require the same resources as Need for Speed The Run, the previous title from the series.
To run the game in good conditions, make sure that you don’t have applications running in the background that would stress the hard drive or other hardware resources. If you have two monitors or more, NFS Most Wanted might not start in fullscreen mode. This will make the game to get stuck every few seconds.
Restart the game. Playing in fullscreen mode will fix this issue.
Graphic tweaks
Here is my hardware and my settings. I3 3GHz, 8 gigabytes RAM, ATI Radeon HD 5670 (1 GB RAM). The game runs smooth and looks great with these settings: High resolution textures (On), Motion Blur (Medium), Shadow Level (Medium), Headlight Shadows (On), Ambient Occlusion (Medium), Reflection Detail (Medium), VFX Detail (Medium), Geometry Level (Medium), Light Scattering (Off).
Some of the settings are by default. I have modified the Motion Blur (turned it lower), Shadow Detail (turned it lower), Geometry Level (turned it higher) etc.
Tips. Motion Blur should not be fully removed as the game will run slower. Shadow Level can be sacrificed. Reflection Detail is a setting that will determine how detailed the cars will look. With the settings that I have mentioned here, the game looks great, don’t be afraid to lower the settings.
What options are consuming the most resources and will make the game to run slower? Ambient Occlusion. Set it to “off” or “medium”.
The second most demanding option is the “Shadow Level”. Lower it until the game runs smooth. Reflection Detail and VFX Detail will also decrease the frame rate a lot if they are set on High.