Honestly, you can't get much better (in my opinion) than a Food Fight/On the Run combo.
Food Fight is part of the Shadowrun Quick-Start Rules and every group I've ever run, new players or old hands, always enjoy it. It gives a solid reason for party formation, allows new players to learn the basics and have fun doing it. On the Run, in my mind is an excellent follow-up when used together. It has the feel of a legitimate mission without (most of) the lethality. That said, the book is laid out terribly so definitely familiarize yourself with the entire book ahead of time. And be wary of the (for you) 22 person fight at the end.
I personally haven't run the Seattle missions against my group yet (starting this week actually), but from what I've read of them, they're great modules but if you're starting with a group that's 1/3 newbies, it might be a bit much if they feel out of their depth. Missions are not kind to the uninitiated.
In any case, check them out and see if you think they're appropriate for your group.