Thanks all for the input so far!

My commute is roughly 20 miles each way. I live in Phoenix, so no big hills to speak of, just psycho drivers! =)

I plan to commute only once a week to start with, then add more days as I get stronger and better at it. I would like to be able to do the occasional weekend touring ride, no more than 100 mi., and of course cruise the neighborhoods with my kiddos.

If I stick to derailers, what would be a simple and effective setup? I was thinking Shimano 105 series for cost/weight/performance ratio. I like the idea of drop bars w/ shorty brake levers, but I'm not sure if that's even possible with disks.

Keep firing away guys! I need your expertise!