BEST FORM OF EXERCISE... RUNNING?

Well what you're doing is completely fine - any cardio is great. And no, you don't have to to have a break between every day of exercising/running; that way, you'd just keep getting set back. You do, though, have to have one day A WEEK that you don't run, so your msucles can rest and rebuild. And kickboxing sounds great, actually - it raises your metabolism up higher and tones/works more of your body. It's not a bad idea, but if you think you would be miserable doing it, then don't. But it wouldn't hurt ot give it a try.