This turned out being an issue with Dell. I'm not sure if it's an issue with all Dells, but it was a problem with 2 that I tested. An XPS Gen 5 and Dimension 3000. I don't know exactly what the problem was, but someone explained it to me as the Dell not being flexible in how it allocates resources to devices, and the ArcadeVGA not being flexible in how it acquires them. I picked up a barebones shuttle as my dedicated mame pc and everything works now, in all it's native glory.
Summary:
* This was not an OS issue.
* This was a hardware issue specific to Dell, and possibly others.
* Shuttles are nice.
P.S. - Why does the XPS weigh 80lbs. when the Shuttle weighs 10?

P.P.S. - For anyone who is interested, the mame pc I built is more than capable, and I got it for $330 from newegg. Specs:
Shuttle XPC case with motherboard, powersupply, fan, and onboard HD audio ($170)
P4 3Ghz processor ($70)
2GB ram ($45)
80GB SATA HDD ($40)