I was going to say, because a lot of what you say is totally not true! It's obvious to me that you really don;t know much about weight loss or fitness.
As far as weight training for weight loss goes, a lot of modern research sugggest that weight training is the most effective way to lose weight (along with a proper diet). It's pretty well known fact. A little research is all you would need to do. Here's a snipped from an article I found with a simple search.
I too keep in pretty good shape most of the time. I have been out of training for a while but my normal practice throughout my life has been to work out everyday for 1-2 hours (depending on the amount of free time I have) and try to get out in the fresh air as often as possible. I actually agree with you on the weight training as good weight loss. If you increase muscle mass you significantly increase daily resting calorie burn rate. While cardio is mostly about what calories you burn while doing the activity. So the result of 1 hour cardio may be 600 calories burned in an hour but the result of weight training can be hundreds more calories burned everyday aside from the hundreds burned actually lifting.
I am not trying to say no one should run, I think I said that I know people who run and are healthier for it. I was simply saying that it can be hard on the body and poor form can make it worse. Weight training can be hard on the body as well, I once pulled an ab muscle and that was possibly the most excruciating pain I have ever experienced. But right up there with that was when I pounded my back into mush running, in running shoes, good running shoes, on a treadmill for about 20 minutes.
I also know that when I have been away from training for a while and become a little plumper for it running can be even worse simply because the total mass moving up and coming down and thus compressing my spine is greater. The very best overall excercise FOR ME is yoga combined with light to moderate weight training and maybe a little cardio thrown in for good measure. Each person has to find the excercise regime that works for them. for some that may mean running. for others running, whether with good form or bad, can cause distress. I know a guy that runs a marathon every day. he weighs about 2 pounds and occasionally gets blown off course by a stiff wind (joking somewhat but he is slight) and he never has any problems at all with his back or knees. I know a guy, 6'2" benches 200+ pounds and can end up flat on the floor with back pain out of the blue. you have to address the issue for yourself. I was simply trying to give GMAC a caution about jumping into an excercise that CAN have negative impact on his back when I remembered him having issues with his back before.
One thing I have personally experienced is the benefit of yoga on core strength (abs, lower back) and how that can really reduce your chances of back injury in the future.