The resolution for the lobby is coded at 1024x768. These black bars appear based on your graphics driver scaling settings. If these settings are set to "scale to fit", it will stretch out and you'll have the full screen, otherwise you'll get the black bars.
I shall link you to Boldpaste2's post about this. This post was made to actually fix the problem with the black bars, but if you do all the steps in reverse it should work as well.
I have recently notice alot of people are saying that they can only see half of the screen, even though there screen size supports the game.
I have recently picked up this problem on my desktop and may have a potential fix. it worked for me anyway.
windows 7 x64
ati graphics cards
-if you find another spec i missed post it here
1) what you are going to want to do is first update your graphics driver. (mine was out of date) then right click your desktop and access the resolution menu. drop your resolution to the lowest setting. then open up your catalyst control center and go under the notebook/ desktop panel properties.
2)if fullscreen is un ticked. tick it. if it is already ticked then you need to change your resolution back to normal. tick something else and save. change resolution back to the lowest setting then spread to full screen.
3)save all settings and place the resolution at the highest setting. then right click wolfteam and hit properties and adjust to maximum window. make sure wolfteam is ran as the admin.
This is also a fix for the black bars bug on windows 7 if anyone knows what im talking about.
let me know how it worked for you.
About the "scaling to fit"- problem; this could also be the cause. You have to manually go to your graphical card settings, you can do this by going doing the following steps.
Rightclick on your desktop and click on properties.
Click on "Advanced" / "Advanced settings", and click on the name of your video card. For me it looks like this:
my apoligies, it's in Dutch, but I'm sure you'll get the point
Click on the button in the window. Says either "Color correction" or "Start <cardname> configuration panel" or something like that.
There you should find the settings.
It might look like the following screenshots (just to get you started a bit):