First thing's first. The resolution isn't "zoomed" it's just a lower resolution and this makes anything on screen look bigger. Anything but the native resolution on a flat panel display, like most people use today, looks horrible(I miss my old CRT, sigh).
I happen to have the free, single player version (there was a promo not long ago) and by the looks of it, it's an Unreal Engine 3 game. Which means that it has some initial quirks. One is the fact that you need to Alt+Tab to get to the game window. Happens with all the UE3 games that I know of with the exception of Mass Effect (the first in the trilogy). The other is the funky way to set up a proper resolution. The following trick usually works:
(make sure steam and the game are closed first)
1) Open the bottle manager, select the bottle where this game is installed and go to the Control Panel tab
2) Select Wine Configuration, click the Launch Selected Item button
3) Go to the Graphics tab and check the Emulate a virtual desktop box, click the Apply button and then OK to exit.
Start Steam, (you should see the Steam window within another window), start the game, go to the graphics options and set a proper resolution to match your native display rez. It may still look funnny. No problem, just close the game and then Steam. Repeat steps 2) and 3) to remove the emulated desktop setting. Start Steam and the game and it should be all fine for you now.
Pro-tip: on some desktops, you can move a window by holding the Alt key and holding left-click on the window, while dragging it around. There is also the option to rebind that key combo....
