We are going, our family is about the same as yours, only my older ds will be just under 4, and my youngest just 15 mths. It was $93 and some change for our tickets, and I've never been, but I think it will be worth it. If nothing else, 3-yo will get to see some characters that aren't normally out in the parade, it won't be as crowded, and it will be a new experience for us.
I have heard that 10/31 does sell out, so you might want to decide and order your tix!
Steph