Thank you @faeran for trying to assist. I appreciate you taking the time to help, I really do, as I am at a complete loss. It isn't the end of the world, by very frustrating nonetheless.
numscreens is set to "1." Everything else is auto as suggested.
Regardless if I adjust screen to \\.\DISPLAY1 or \\.\DISPLAY2 it always opens on the marquee screen. I don't understand it. My marquee display is a computer monitor connected by display port->HDMI and the main display is a TV connected by HDMI->HDMI if that makes a difference. I even turn off the marquee screen (not unplug) and MAME games still try to run on the marquee screen (nothing shows up on the main display) This happens whether I launch a game directly from MAME or via Launchbox/BigBox.
So my marquee is enabled through BigBox. (I hope that answers the question) Options>General> Display 2=Main Display, Marquee Screen=Display 1. It doesn't match the Windows configuration, but I don't much care as it works. When I open a different system and load a game, say Super Nintendo (retroarch), the displays are correct. When I get to the platform menu and hover over Arcade, the marquee "Banner" shows correctly on the marquee screen. Even when I select Arcade platform and select an arcade game it will load correctly with the game on the main display and the marquee on the marquee screen. Then when the MAME game loads and takes over it switches the game to the marquee screen leaving the main display black. It also crashes the system as I believe that the marquee banner and game are trying to load on the one marquee screen. Very weird.
Any thoughts?