Just want to add my 2 cents on this topic. There was a similar post to this when I was going through my set up (about 3 months ago). After investigating several of the frontends, someone mentioned Emulaxian. So, I tried it. Let me tell you ... if you want a true "arcade" experience this is the frontend. I know my friends have been totally impressed with it. There is nothing like the looks on their faces when you launch it and they are standing in the middle of a virtual arcade!
Here are a few words of warning though. Emulaxian takes a little while to "learn". There is a lot of configuration, but if you stick with it, you will be very happy. There is also a lot of customization you can do with downloads from the 3darcade website. However, you can run it "out of the box" and that is what will hook you. Well, it hooked me. Also, it would seem to me to take a little bit of horsepower to run. I am running Windows XP on an Athlon 1GHz with a ATI Radeon 8500LE video card to a JVC 27" TV via S-video out, and it is awesome. I am really happy with the results. Sure, it may not be perfect, but it looks pretty good. Yes, you do have to use the command-line Mame but setting that up is really simple inside the frontend.
Give Emulaxian a try ... as I said my 2 cents.