is walking good enough?

if i walk everyday for 20-30 minutes will it help me lose weight? i cannot run or jog yet. i haven't been exercising regularly like i used to

Depends on your goal - performance-wise you'll plateau pretty rapidly, but as long as you control calorie intake any activity is good for you. There's several posters here who've lost significant weight just walking and counting calories - the majority have also taken up other forms of exercise after getting to a point where they felt ready for more, but you absolutely can get a very good start by walking.

I have lost 20 lbs so far, mostly walking and counting calories. 

But Melkor is right - your performance will plateau quickly.  Meaning that you will reach a point where you really can not progress further in your sport.  You will also find that after a couple of months you are not burning as many calories doing the same exercise.

But the whole point of making a lifestyle change is to do something you can stick with for life.  If walking is something that you can commit to - than stick with it.  No matter what you will always have some way to stay in shape :)

Now a little inspiration:

My boss has lost 80 lbs walking and counting calories.  He has kept that weight off by walking too.  He is not content to just shuffle along.  He challenges himself to walk further - do it faster, take more hills etc.  For his maintenance he walks 4 miles daily on his lunch break.  I walk 3 and use the same challenges.  I have about 25-30 more lbs to go.  (see me shrink)

The challenges help keep you from plateauing and keep your walk interesting.  You might even consider borrowing a dog a couple of times a week.  A nice pooch that pulls with enthusiasim will give your whole body a work out and the dog will love it too.  I borrow my co-workers dog every Thursday.  We have a great time.

years ago I lost 55 lbs just by walking and counting calories so yes its possible.  I too found that at first because I was so out of shape the lbs melted off quickly, but as the lbs went away, my health improved it was harder to "workout" so had to walk further faster and find hillier routes. 

Get a good pair of shoes and hit the pavement, paths or walkways and enjoy it.  Later just be prepared to want to and need to add to it

Actually, it all depends on your activity level and diet beforehand.  If your goal is to lose weight, and you are on a restricted/defecit caloric diet..you will lose weight! Exercise will add to the weight loss. Exercise alone will not help you lose weight if you continue bad eating habits. Proper diet nutrition without exercise can definitely help you lose weight if that is your only goal.

Walking is one of the best methods of excercise! Do not be fooled by the idea of jogging 10 miles! When you run without you're body being ready, your muscles may be injured. As long as your walk is brisk and energetic, there is nothing wrong with that! Try to move your arms as you walk, and maybe put your shoulders back and stick your stomach in. This way you are excercising your whole body! You can even walk with a group of friends. I would completely support walking!