It lists right on that linked page what cards work with the dongle. You could pick any of them up for less than $100 if you look around.
Yeah, I saw that and even mentioned it in my original post.  I guess I was just hoping that the vendor had incomplete or incorrect information.  Looks like dynamike has a 64MB version of the same card that he tried and failed with.  That's what I was looking for.  Confirmation.
On the matter of finding a card that will work with the dongle, I agree the cards are plentiful and I know I can find one (fairly cheap, even -- saw one go for $28 plus shipping on ebay 20 minutes ago).  But I am so strapped for cash now that anything more than the cost of the dongle, cables and shipping is more than I can justify for a project that I am not even sure I want to do.  As I said, not even sure if I want to lose the resolution I have with the PC monitor.  For now, I am think I am going to trudge on with the 19 inch VGA that has served me well so far.
I'm afraid I can't help you with your DVI out question, but I just wanted to add that it is definitely possible to use MAME32 on a TV (I did it for years over an S-Video connection).  You can increase the font a bit or bold it for better readability.  It's not as sharp as a PC CRT of course, but definitely doable with some configuring.  
Thanks for that.  I was thinking if I boosted font size, I might get away with it but I wasn't holding my breath.
Thanks for all the replies...
Bumble