How to lose 20-25 lbs. safely and as quick as possible?

Ok, let me start off with some Info. I'm 27F, I weigh about 155 and i'm 5'4. For the past 2 years, I've went back and forth between 152-157 but I cant get past it. I've never had a weight problem til' a couple years ago. Its depressing me and I want to be my old self again. I'm also a full time Nursing Student, but I still have time to eat well and excercise. I need advice on what to eat, what I should do to workout to lose the weight quickly (my problem areas are my legs and stomach..im not fat, but I need to slim up)...how much I should eat. Should I start out with a walk/jog for 45 minutes 5x a week, or do a workout video and if so, which one? What are some good foods to eat? And is there any food programs that are good, atkins, south beach ETC.? I know I sound clueless, but Im tired of not being able to get under 150, its just ridiculous. I will admit, I dont really excercise, but im ready to get myself in shape and I just need help-advice. Thanks.