Helium Frog is wonderful, even if it crashes, it saves your animation, and you can import your frames as individual frames (great for editing) or as a video file. GIMP is without a doubt the best photo editing program out there that's free. Audacity is also fantastic.
Sony Vegas is what I am currently using; yes, it costs $100, but if you're only going to be doing this project for a little while longer, head over to the Sony Vegas website and download the free trial version. No limitations, except it will only work for 30 days. You can do everything else that Sony Vegas does though; it was extremely useful for my last school project, when I didn't have the money to buy a program.
Hope this helps!
kcirb-- its brick backwards.
Youtube