Supreme Commander 2

Simply select your resolution from the options menu.
(A secondary monitor connected to your main graphics card can be used to display the strategic map. Each monitor can be any AR/resolution.)

Settings are saved in
(XP) C:\Documents and Settings\\Local Settings\Application Data\Supreme Commander 2 Demo\Game.prefs
(7) C:\Users\\AppData\Local\Gas Powered Games\Supreme Commander 2 Demo\Game.prefs

Edit it with notepad and scroll down until you hit options. Change the primary_adaptor = '' field to your resolution and refresh rate (i.e. '5040,1050,59'). Should run fine after that.

Screen Change:
Vert-

Free camera height and angle help taking advantage of wide & multi-monitor displays, and the strategic map is Hor+/Vert- in Surround. Nevertheless, SC2 is essentially a Vert- game.