the monitor formats have changed since Armed Assault and Operation Flashpint
I suggest adding a few new aspect ratios to the dropdown menu in the video options:
21:9 = some new screens have this aspect ratio.
for triple screen gamers I think the following aspect ratios are quite common
16:3 = 16:9 x 3
24:5 = 16:10 x 3
Right now some have to edit the config files to get the right aspect ratio
I think the above options would solve that issue for most people.