I agree with BikeLady - as a beginner don't worry too much about individual things, take it easy and just get out there and ride.

TITS or Time In The Saddle is all you need to concentrate on to start with. It'll help you get used to your bike, get used to the road and if you're interested in weigh loss, there'll be a few pounds lost in the process. As you get stronger you can gradually start to concentrate on more specific things.

About pedals, if you don't feel ready for clipless ones yet, then why not try out the toe- clip & strap combo for a while and see how you get on. ( it really does make things easier.)

Happy riding