Congratulations on your decision to improve your life. Improving your diet and lifestyle will be so rewarding. I am so excited for you!!!!!!!
Drastic change is not really recommended for long term weight loss, (meaning keeping the weight off). 30-40 lbs is not THAT hard to lose. By no means am I saying its going to be easy, (especially with junk food around), but it can be done. I lost 110 lbs with the help of gastric by-pass and A LOT of exercise.
In my opinion, these are the two most compelling factors when it comes to weight loss; sugar intake and exercise. If you were to do just a few min of exercise each day, you would see a difference. And if you were to cut out artificial sugars from your diet you would see a HUGE difference as well.
Just start with walking. Just walking. Really, this could motivate you to do more each day. Or bike riding or swimming- something you could track and increase as you see fit. Cutting sodas alone will do wonders. Or switch to diet at first, then eventually try to eliminate. Just try no candy or sweets, of any kind, for one week and you will see the difference in your body.
You will get tons of advice in this area, and as always, check with your doctor. The sugar thing may make you shakey and stuff the first week, I was really suprised- and so were my sis-in-law and her husband when they gave up soda with me!!
I have had amazing results! But I was VERY strict with myself for a long time. I still enjoy exercising a great deal! Best of luck and PLEASE pm me if you need anything else! I may even muster up the courage to share some before and after pics! lol... I could talk about this subject for hours but don't want to bore you poor souls to death! hehe...