Also, on Ultimarc's arcade monitor FAQ, they say that using a TV is a horrible idea. In this board's FAQ, TV isn't mentioned, so what's the deal?
Naaaah...don't listen to 'em. I use a 24" RCA via s-video, it works great. The drawbacks are
1) VPinball/PinMame suffers most, but are still good
2) Vector games are next, not nearly as crisp as a CRT, but still very good
3) Raster games are fine
4) Small print in any of the above is difficult to read
I've never seen an arcade monitor in action, and you can't tell what you'll get by looking at pictures. Overall I'm very pleased with the results of my 24" RCA using s-video. As MinWah pointed out, this arrangement is relatively inexpensive (got my TV scratch & dent for @$129) + TV out vid card @$50, and your PC/Windows will work no problem on the TV.
If you have any specific concerns about the TV set-up I'll be glad to help. Don't be afraid!