I haven't tried this program out, but I do know the power of vector graphics. (I use a program called Xara for most of my 2D animation.) You can intersperse little .wmv animations with your movies -- maybe for a cartoon title for a birthday video.

This company decided to discontinue development and let this program go for free. Here's the link to the home page and download:

http://www.creatoon.com/index.php

Caution: For me, their server was really, really slow. So, I had trouble watching demos and tutorials. If anyone gets the time to try this program out, please provide feedback here.