If you're playing a game in that ratio you're going to need a really high FOV for things to look right compared to 16:10 or 16:9. 90 FOV is ideal for 4:3, you need higher FOV the closer to 16:10 you get, and 120 is typically the highest allowed in some games. I don't even know what a game is going to look like in 21:9 fullscreen without some hack or native support for something like 160 FOV.
No.is there such a thing as a 1920x1200 144Hz refresh rate?