We had our 2 year old's birthday party at My Gym (Bathurst/ Rutherford). Parents and kids had a fabulous time, and the staff were amazing in coordinating the kids, activities, cake, food, _everything_.
We attended other fun birthday parties at Dreams Playland on Rutherford Road, and Gymboree in Promenade and some in the home with more than just 2 friends. Organized activities (circle time, singing and puppets) were a big hit.
I think at age 2 it doesn't really make a difference as the kids don't play with each other, but more 'next to' each other!