With the exception of two people, none of my friends like anime and I can't really see them ever liking it. Some people just can't get into it.
But if you really want to try to get your friends into it, I suggest Cowboy Bebop. It seems like a series that is good enough to stand on its own, even as just a show, not an anime. Its stories are so entertaining that I could see someone who isn't into anime at all liking it.
I say try to find something pretty general, and don't go into specific genres too much right away. Unless they tell you they are into romance, drama, horror etc.
So I'd suggest Cowboy Bebop, Trigun and maybe something like Love Hina. Nothing with too much ecchi either though. That's how those stupid "all anime is porn" crap gets into their heads.