Honestly? If they are completely new to the system, what you ought to do is build their character for them, and then give them a cheat sheet with what they roll in certain situations. With a good cheat sheet, anyone who has any experience with RPGs should be fairly well off until they get the hang of things.
What is more important for newbies is to give them a primer in the ATTITUDE of shadowrun. In fantasy or superhero RPGs, you are heroes, or at least people who can get into knock-down drag-out fights with powerful creatures and expect no consequences. You kill things, take their stuff, and live large. In other words, you act in all the ways that will get you killed in Shadowrun.
I'm going to be starting a group of complete newbs on Shadowrun soon. The players are my weekly D&D group, and I'm running the game to give our DM a chance to take a break from the big chair. I handed everyone the 'History for the Reality Impaired' section of the core book a couple months ago, so they have a chance to get that through their heads, and I've given them copies of the quick-start rules. Most importantly, I made sure to tell them, in no uncertain terms, that they were not going to be heroes. Doesn't mean they sell their buddies to Tamanous, but you're not heroes. The Sixth World is not a nice place. Racism and sexism are alive and well, even in the shadows. And everyone has flaws. Could be an addiction, or you piss off fire spirits by breathing, or whatever, but every character has flaws. The other point I made was that if you have to change clips twice in the course of a firefight, you're doing something horribly, horribly wrong.
Proper use of cheat sheets can help people out, until they learn the system themselves. What is most important isn't the character type the person's playing (though some people are better suited to playing street sams than faces, natch) but indoctrinating them into the history and attitude of the setting is more important.