All personal preference, of course, but..
Baytona USA, I can NOT STAND that effin' attract sound.music/noise. Arg. (Used to have two of those in one of my arcades.. hearing that "Day-Ton-A!" got really old, really, really quickly.
Outrun is fun, I could enjoy that.
Crusiin' <fill in the blank> is not bad, but car handling sucks, and there's a very annoying bug in some of them that causes you to hit an 'invisible' car. Argh.
IMHO, Rush is the best line of racing games - to me, the car handling is best, and the course 'shortcuts' are fun as hell. Yes, I have two of these (Alcatraz versions), linked and soon to be online to race against others.
Some of them (Rush, at least?) you can interconnect over the internet and race against people states away (assuming you can get a VPN set up fro Rush, not sure about the others..)