I've read a majority of both books and I try to break them down in my own words.
Dr. Oz's book is best for those who want to learn about all the bioliogical aspects of eating and the reasoning behind it. He goes into detail regarding why humans like sweets, what are the affects of stress and your eating habits etc. Also After you learn all the biology behind eating he goes into his weight loss plan. I think it starts of w/ a 14 day program where you walk everyday and follow his rough meal plan guide ( This is pretty helpful to see what kinds of foods you should be eating and also the portion size) He also encourages that your walk at least 30 minutes every day and also do some strength training which you can find on his website (realage.com for free by the way) Then after that you just keep up w/ the program and you're set.
Oh also he does a grocery list of things you will need for the beginning of the plan which is pretty helpful.
Now Bob Greene's Plan is more laid back but very heavily endorsed (I'm assuming b/c of all the name dropping in his book) by big food companies (Meanwhile Dr. Oz's is not.)
He basically asks you to answer 3 questions. Which range from why you want to lose weight, why haven't you and something else.
Then he breaks it down into 3 phases that can last awhile, i.e. Phase 1 can last for awhile if you are losing weight. He is more flexible about your exercise regimen and it's easy to follow.
I liked both books b/c of diff things and you can always try your local library to see which one you like and buy them after.
I hope I didn't bore you to death and both books are worth the read and can def. help anyone get on track.