Launch Bioshock 2 through Steam.
Get to the Bioshock 2 Main screen like in this picture .
Now Select Options, Graphics Options, Graphics Resolution, then select 1280 x 1024.

-This resolution makes your FOV A LOT better, but it lowers the quality of the game.

-However, If you happen to have a NVIDIA geforce graphics card, there is a way to make it look beautiful with the fov fix and in the next few steps I will be covering how to do this. NOTE: There is probably a way to do this with AMD as well but I don't have AMD graphics.

Ok so you have the fov fix, now time to make the game look amazing IF you have NVIDIA graphics.

Firstly, close Bioshock 2 Multiplayer.
Then, Go to steam where you are able to launch the game, but dont launch it.
On the right side there should be a settings icon. Select settings, then properties, then General, then there should be a empty box titled launch options. Type "-dx9"

This makes the game look very nice on the eyes, however the fov resolution and the dx9 dont mix well. In order to use both at the same time complete step 4.

The fourth and final step.
Get to your pc homescreen
On the main screen of your pc, go to bottom left type bar and type in "NVIDIA Control Panel" and open it
On the left hand side look for "Adjust desktop size and position"
Switch your scaling mode to "Full-screen" and check the box that states "Override the scaling mode set by games".

Now you are done, enjoy Bioshock 2 Multiplayer in all it's glory :)