Game Resolution Switcher rignt now will launch Battlefield 2 at whatever your resolution is set to.

Though to be honest, it's not doing much special. To run Battlefield 2 at a resolution beyond the limited ones in game, you simply add:

+szx 1280 +szy 720

to the executable. Easiest way to do that is to right click the shortcut and hit properties. Odd are, there are other commands there as well, like +fullscreen 1 and such. No hacks, no fuss.

Do be warned though, Battlefield 2 does not have proper support for widescreen displays. Running it at any aspect ratio other then 4:3 results in what you see being cropped. People are hoping support for this is added in soon, as games like Half Life 2 and Doom 3 simple work and asjust the aspect ratio on their own, requiring no FOV adjustments.