I lost 40 lbs in a year, so I'm pretty sure 50 lbs by Feb 2010 is quite doable.
I did Atkins by-the-book and didn't workout all that much my first year (when I lost the 40 lbs). I did some walking on my treadmill and a few crunches 3-4 days a week for maybe 30 minutes. It wasn't until a few years ago that I really got into exercise - if you can't go outside and can't afford/house a treadmill or elliptical, then go for workout dvd's. I have a ton and love them - I mix them up with walking/jogging. They work different muscles, too, so I know I'm working everything. Plus, I hear from other parents that their children often want to join in with mommy. Most of these dvd's are fine for kids (unless you get into weight training or really intense stuff), so it could be a good family activity.
Bears? Oh my... I'd be the crazy lady running around outside TRYING TO FIND the bears! ha! Of course, if I had small children I may reconsider. hee.