I own a dual-vga MX board and that Geforce FAQ is wrong.
The MX boards support overlay in the 2nd display. You need turn it on in the "additional graphics properties/taskbar utility" tab. You'll see a button show up with the 2nd output on that says "full screen video center" or something like that. Hit that button and you'll have all sorts of overlay options for the 2nd display.
Also, if you folks want to output Macrovision protected DVDs from your video outputs, download TVtool and turn off Macrovision.
TV Tool