Dear New PTO, OLD School:
We are having a few similar issues with our PTO and school relations. However, our school Director is probably the opposite of yours, she is very nice and agreeable, but sometimes it detracts from real progress being made.
I think we did a good job of "winning over" the teachers and director by starting the year off with a teacher appreciation luncheon around Thanksgiving. (It was so successful, we have another one planned for teacher appreciation week in May.) It takes some organizing, but we posted sign-up sheets requesting various items from the parents: entrees, drinks, desserts, paper plates, tableclothes, favors for the teachers, and volunteers for set-up, clean-up, and some parents to make "reminder" phone calls.
You could also try to work with your principal's style. We invite our director to our meetings and present new ideas to her by stopping by the office and saying, "This parent had a great idea, it goes like this, what do you think?" She likes that we check with her. We had one instance when we spent a lot of time on a fundraiser that involved a friendly competition between classes to see who had the most participation. After painstakenly writing class numbers on hundreds of flyers, the director told us that she and the teachers did not feel comfortable with preschoolers "competing". Had we given more notice of how the fundraiser was set up and gotten feedback, we would have saved ourselves some trouble.
Hope that helps a bit. Good luck!