Hi JHGould5607,
Sorry for the late answer. This monitor is a tri-sync one, you may try your luck with the preset settings for WG D9800. There's a menu in the live-cd gasetup labelled "Video setup", where you can specify this setting. You must not force any resolution mame.ini, GroovyMAME will pick the right resolution depending on your monitor setup.
Hope it helps.