Doing IB will help IVY admission. It is very competitive to admit into Ivy league school. If you choose the highest level course in IB and have good marks, it will definitely help. If the mark is not good, or you did not choose highest level course, it might not help.
Lisgar or bell offer AP course as well. Same idea.
Being in IB is not all for academics, it is more for your capability to manage the time, and be ready for university challenges etc.