I had a similar problem a couple of times with NFS shift. You need to select a different resolution (lower), maybe with AA AF off, accept and exit the game. Then try again, start game, go to play. I saved a copy of a working graphicsconfig.xml file located in :
my documents
NFS SHIFT folder
because, it seemed like I could get in a funky loop and the game would just keep crashing.
So if you like, open your graphics.xml file in notepad, copy everything in here , from mine. The game should then start at "1680" height="1050"
<?xml version="1.0" ?>
<Reflection>
<class name="BRTTIRefCount" base="root class" />
<class name="BPersistent" base="BRTTIRefCount">
<prop name="Name" type="String" />
</class>
<class name="GraphicConfigData" base="BPersistent">
<prop name="Mode" type="Fct" />
<prop name="Vsync" type="Fct" />
<prop name="Windowed" type="Fct" />
<prop name="TextureFilter" type="Fct" />
<prop name="TextureResolution" type="Fct" />
<prop name="Brightness" type="Fct" />
<prop name="CarDetailLevel" type="Fct" />
<prop name="TrackDetailLevel" type="Fct" />
<prop name="ShadowDetailLevel" type="Fct" />
<prop name="MotionblurLevel" type="Fct" />
<prop name="EffectsDetailLevel" type="Fct" />
</class>
<data class="GraphicConfigData" id="0xBB11E0">
<prop name="Name" data="" />
<prop name="Mode" adapter="0" width="1680" height="1050" antialias="0" refresh="60" />
<prop name="Vsync" vsync="0" />
<prop name="Windowed" windowed="0" />
<prop name="TextureFilter" texturefilter="1" />
<prop name="TextureResolution" textureresolution="2" />
<prop name="Brightness" brightness="10" />
<prop name="CarDetailLevel" cardetaillevel="2" />
<prop name="TrackDetailLevel" trackdetaillevel="2" />
<prop name="ShadowDetailLevel" shadowdetaillevel="3" />
<prop name="MotionblurLevel" motionblurLevel="3" />
<prop name="EffectsDetailLevel" effectsdetaillevel="2" />
</data>
</Reflection>
This won't effect your profiles