Bunch of questions here. :) I'll do my best to answer clearly.
Yes, you need rest days. Running is a VERY high impact exercise, even on a treadmill, and you shouldn't do it every day. On your non-running days, you need to be strength training to offset the lean tissue loss you'll be getting as you lose weight.
How long you workout doesn't matter; you'll be aiming for the same rate of weight loss whether you work out for 30 minutes or 2 hours. However, if you're like most people, you don't have 2 hours to waste when 30 minutes will give you the same benefit. Running intervals for 30 minutes and burning 200 calories is a better use of your time than running slowly for 2 hours and burning 200 calories.
More is not better; you aim for the same weekly weight loss goal no matter how much you exercise, so the more you burn, the more you eat to compensate and keep from eating too few calories to sustain your activity.
Writer, mother, wife, and breadwinner. I love to run, but running doesn't love me, so I'm switching to my low-impact bike.
I'm not pregnant, just fat: My blog. fatnotpregnant.blogspot.com/
| current weight: 186.4