Text is literally unreadable so I can't find the right option in the settings menu. Tried multiple launch options to no avail. restarted steam and the computer, nothing.
You should give at least some information about your system, and the context, we're not psychics ;-) Was it running fine before, is it the first update since EA, that sort of things.
1) What I'd try is renaming the following file, to force the game to reset the entire configuration:
c:\Users\\AppData\LocalLow\Tactical Adventures\Solasta\UserPreferences.xml
(%USERPROFILE%\AppData\LocalLow\Tactical Adventures\Solasta\UserPreferences.xml)
If that doesn't change anything, you could try and edit it, and change those two parameters under UserPreference/Settings/Graphics (those are my settings, just adapt to yours):
<Resolution>1920 x 1200 @ 59Hz</Resolution>
<FullScreenMode>FullScreenWindow</FullScreenMode>
Keep the original file just in case, to put it back in place.
2) Unfortunately I see this program also has the bad idea of using the registry for settings *sighs*
So there's that to modify, but unless you are very familiar with the registry, I wouldn't try because if you do something wrong it could break your entire system.
If you are familiar, you'll find where it is.
EDIT: stupid forums are changing my post, fixing...