How to play Burnout Paradise on two screens without "unifying" the desktop?
Solution 1:
I've not tested it with Burnout Paradise, but as a general productivity tool I can definitely recommend Ultramon: http://www.realtimesoft.com/ultramon/tour/windows.asp .It has a variety of features around window management/taskbar configuration but in-particular it can add a button to application title bars that will maximise them across multiple monitors.
You'd have to purchase it but I think they have a trial.