howdy Vette!
I think we're both mirroring each other with our cab build progress :-) Tell my your building a converted Neo-Geo MVS 4 way and I'll pass out :-) We should get together and swap stories of our build, you in the New England area? I'm in South Eastern Mass...
First thing, throw away that ATI card, bit e the bullet and buy an ArcadeVGA from Andy. WinXP and MameWAH just plain don't like to be set to different horz refresh rates.... $89 is a small price to pay for being able to boot with the monitor on and go into the BIOS without worrying about blowing your monitor. I bit the same bullet that you'll be biting evenutally, might as well do it and get it over with.
I also went the DOS route at first. I figured, heck, I've been using DOS all my life, I learned DOS 3.1 early on and progressed up to what I know now.... should be a piece of cake and nostalgic for me to boot! I remember trying to get every ounce of memory out of DOS. My Best friend, who passed away in 2001 and I miss dearly, could always get a few more KB out of his system than me, but he tried many many more things than I ever would want to... we both really enjoyed DOS back in the day.... but I digress... AHEM sorry <grin>
Going the DOS route was a nightmare, sure I got the sound card and everythign else working fine in DOS, but then ArcadeOS wouldn't work with the sound card, once I got that working then Advance MAME wouldn't work with the sound card.... oh yah then there was the game listing issue with ArcadeOS and XML2INFO that wouldn't work under DOS (that's been fixed now BTW).
I bit the bullet and formatted and put XP pro on the machine.... works like a champ. A few snags along the way though but ArcadeVGA is an awesome card and i highly recommend it, mine has an issue but Andy from Ultimarc is taking care of me no problems there! Thanks Andy!
I'm running an INtel PIII 800 - 133FSB w/ 512 PC100 RAM, XP pro, MameWah and using mamewah setup too....
You'll use the straight windows command line version of MAME, not dos mame....
You'll be able to run daphne, z26, NES emu, etc a whole slew of emulators dude! MameWah's the stuff legends are made from :-)
Good luck with your cab!
Mike B