Yep. I've been there. It doesn't appear to support bitmap fonts and I can't get it to recognize many of the truetype fonts that I tried. For example, I couldn't get Courier New to work. I tried courier, Courier New, and "Courier New" (in quotes) and couldn't get it working. I don't see any rhyme or reason why some fonts work while others don't.
Out of the ones that did work, tahoma seems to be the most legible on my interlaced screen but the point size is still slightly too small for it to be completely legible.
Things that would make Attract-Mode more usable for me...
1) some way to quickly cycle through each of the fonts on the system without editing the config and restarting like a "font preview" page
2) a way to adjust the font size
3) bitmap font support (I know, not likely)
GroovyMAME support forum on BYOAC