As others said, it's a ton of walking. Do the best you can to get in the best shape you can. I know my opinion may be different than others, but taking a 2 mile walk every day for a month before your trip will be of very little benefit...IMO most of the benefit you'd get from that is a placebo effect. When you take a 2 mile walk, it'll take you anywhere from 20-40 minutes depending on your pace. That's not at all how WDW is. You'll walk 5, 6, 7 miles over the course of 4, 5, 7+ hours. A lot of that time you may be standing as well. So they're really not comparable. Don't get me wrong, taking a walk is never a bad thing, but it's really not going to do a ton for you when preparing for WDW.