Quoting Executionista:" So I really need to lose just under if not 100 lbs. I'm 5'2" and about 215. I've never been really skinny. ... [snip!] ... fit unfortunately and I have a 498 budget a month for food per. foodstamps.] I also walk a lot, which doesn't seem to do much."
I've been doing weight watchers. You can look online and find point values and online calculators and stuff to help you, and I find it works wonderfully. It lets me limit my food without feeling deprived. I'm also 5'2 so I know how hard it can be to be short and have a lot to lose. When I had my son I was over 200. I think around 220. I got down to 180 where I sort of sit most of the time without really trying, but I've worked really hard to lose almost another 20 since then.
Weight watchers has been a HUGE help, and if you can ever budget it, I think the meetings are really really great. It's a huge motivator to go to a meeting and be around others. However, as I said, the plan can be done without the meetings also, and it still works well.
Walking is good, but you do need to push yourself! Sometimes people stroll leisurely, and it just doesn't do a lot. You have to walk to the point that you raise your heart rate. I've gotten into jogging and I love it! Also, lifting weights is huge. You loose less "weight" but you lose inches very quickly!!
Lastly, don't push too hard. This is something you're going to be doing for the rest of your life. This means don't rush into it by trying to jog a mile every dday and eat nothing but salads. That isn't sustainable. Make changes gradually and really remind yourself that these are changes for the long haul. It helps so you don't burn out because you did too much too soon.