Hi Madhuri6,
Those two books are remarkably similar to one another, so you would be fine working with either one. Since November is less than 3 weeks away, you're clearly planning to take the GMAT sometime relatively soon. If you're looking for advice beyond which OG to purchase, then it would help if you could provide a bit more information on how you've been studying and your goals:
Studies:
1) How long have you studied?
2) What study materials have you used so far?
3) How have you scored on EACH of your CATs (including the Quant and Verbal Scaled Scores for EACH)?
Goals:
4) What is your goal score?
5) What is your exact Test Date?
6) When are you planning to apply to Business School?
7) What Schools are you planning to apply to?
GMAT assassins aren't born, they're made,
Rich