EDIT: changed it from big pictures to links. Make sure you expand them to their full size when you look at them.
Okay... now that i was sober, i thought lets give this a good test.
1. "D:GamesBattlefield 2BF2.exe" +menu 1 +widescreen 1 +szx 1920 +szy 1200 +fovx 106 +fovy 106
http://www.xs4all.nl/~skinny1/screen005.jpg
FOV settings don't do much here.
2. "D:GamesBattlefield 2BF2.exe" +menu 1 +widescreen 1 +szx 1920 +szy 1200 +fovx 90 +fovy 90
http://www.xs4all.nl/~skinny1/screen006.jpg
Here the FOV settings don't do much either.
3. "D:GamesBattlefield 2BF2.exe" +menu 1 +widescreen 1 +szx 1920 +szy 1200 +fovx 60 +fovy 60
http://www.xs4all.nl/~skinny1/screen007.jpg
Definately, fovx and fovy don't work. The 3 screen are all the same.
4. "D:GamesBattlefield 2BF2.exe" +menu 1 +fullscreen 1
(this is 1600x1200, notice the difference between +widescreen 1 and +fullscreen 1)
http://www.xs4all.nl/~skinny1/screen008.jpg
Now here is the interesting part. We already know that vertically we can actually see more in 1600x1200 than we do with the widescreen settings. This is visible in the smokestack to the right.
But, if you look closely to the side of the smokestack, you can see just as much horizontally if not slightly more in the 1600x1200 setting than you do widescreen! This is visible when checking the / stilts of the smokestack.
Now, the ONLY THING that i can see that is actually widescreen 3d, is the weapon and arms. If you check the left arm, you can see more of it. The rest of the 3d is just slightly zoomed. This is also visible in the text in the middle of the screen when compared to the knife that is being balanced.