I usually just still use good old mameui (was mame32). There are 64bit and 32bit versions.
I only have two bitches about win7. Media player is broken and likes to corrupt mp3s that have musicbrainz data in them. Also the smashing up of tasks into the taskbar. 'is that this visual studio or that one'. Pain...
Other than that it they really fixed vista up nicely. They actually made it so it doesnt take over your computer at random points in time.