Dark_Pheonix0720 Sorry for the late reply; I've been away from the forums for a while.
What I'm wondering is, if you change a graphics setting (other than fullscreen/windowed or the resolution) while at the Main Menu, then quit to desktop, then launch the game and load a save without changing anything else, what do you see? This is the safest way to change settings and the only one I use.
I'd try this in both fullscreen and windowed modes. If the game won't open properly after you've changed a setting, you can delete Options.ini, in Documents > Electronic Arts > The Sims 3, to revert all the settings to the defaults. You can also edit this file to set fullscreen to 0 or 1 so you don't need to launch the game just to flip the one setting.
I can help you get your graphics card recognized as well, if you're still interested. This would only help with the unrecognized GPU, probably not the other error.
As for your dxdiag, there's nothing particularly alarming. However, it did crash as it was running. That might not mean anything, but let me know if you're seeing other system issues.