Baseline (Widescreen) Solution & Issues
This game supports widescreen natively. Just select your resolution from the ingame "visuals" menu.
This game is Hor+.
The game automatically uses the correct aspect ratio for your resolution. However, the FOV in either directions is proportional to the resolution in either direction. That is, 1280x800 is hor + compared to 1024x768 only because the horizontal resolution is larger. Compare 1280x800 and 1280x720, and the 16:9 resolution is vert - in comparision.
The HUD scales correctly, as can be seen in the above screenshots.
The game only has one intro FMV. But the game automatically switches your resolution to 640x480 before showing the FMV, so the widescreen handling is irrelevant.
Ultra/Super-Wide (21:9/32:9) Specific Solution & Issues
Eyefinity / Surround Specific Solution & Issues
4k UHD Specific Solution & Issues