Yo, Amigo! Como esta usted? You sound like me just a few years ago. I cut my teeth on Ken Kifer, and I will probably still be learning from folks like him until they throw dirt on my face...

I started out fitness walking. It's a good cardiovascular workout which subtly builds your heart and circulation, which is foundational to cycling. Once you start cycling, your legs will begin to adapt and your walking will turn out to be a great help.
In fact, walking is still my preferred cross-training exercise.

A good plan is to alternate cycling days with walking days. As you said, the two exercises use different muscles, so while you are doing one exercise, the muscles from the other are given some recovery time. A 24-hour recovery period will add pleasure
and performance to your rides. If you ever don't feel like cycling, it's o.k., just take a day off. You have the rest of your life to gradually improve. One mistake many of us have made is to overtrain (push too hard too often for too long). Then it may take weeks to recover. So just take a day on and a day off (walk on off days.) The object is to enjoy anyway, right? :thumbup:

(Jeff Galloway, a fellow Atlantan and former Olympic long distance runner, said on the local news the other night that he finds his best performance when running/walking intermittantly, that is, on the same outing: run, walk, run, walk. That's not exactly swapping days, but it may be similar.)

Atlanta has some great cycling opportunities and some great challenges. My bicycle commuting advice is to learn proper road cycling skills, if possible by taking an Effective Cycling course. Also, don't venture out onto roads you don't feel safe on. It will take time for you to build your confidence in traffic (it did me.) Just tackle each challenge as you feel ready for it, arming yourself with the knowledge afforded you by those who are already doing it, like John Forrester and John Allen. It's like driving--at first you are kind of scared out there, but as you practice you gain confidence. Don't feel embarrassed about not jumping right out there onto a busy artery in rush hour. It's probably your conscience warning you that you aren't ready, my friend! Nevertheless, in time you will be sitting in traffic with your bicycle,
and hear comments from open windows like, "Hey, you're not a car!"

Remember, you have an advantage over motorists: you have plenty of driving experience, but they (usually) don't have any cycling experience. Make the most of your greater knowledge level. And read all you can about the subject.

(P.S. In the summer, check the ozone levels and avoid cycling if they reach excessive levels. This will benefit you in the long run.
Call (404)362-4909 for the hourly report for Atlanta. When the recording starts talking, press #1 to bypass the junk and get to Atlanta's report. Levels over 150 should be avoided in my opinion.)
I am so glad to have you in these forums, Kevin!