For all you new animators just starting out with Flash, here's some advice:
Start slow and be patient.
When I was 12 I watched tons of Flash animation on NG. I was a typical NG flash animation lover. I thought I had Spielberg-esque ideas for Flash cartoons and wanted to get it for myself so that I could make my own masterpieces.
I never actually got around to buying Flash, but six years later, in a technology class in my school I got to use Flash for an assignment. I was so excited that I would be able to make my own super cool animations.
My first time with Flash, after a full hour I could barely get a stick figure to move his arms. It took me 10 minutes to send a yellow circle from one side of the screen to the other. During a stick animation I made, countless times I had to follow instructions exactly right otherwise the animation and movements wouldn't work properly.
Contrary to what I thought, animation requires more than an ability to draw and write. It requires a knowledge of computers, a good memory, and above all, patience.
That brings me back to my original point. Be patient with Flash. I am not in any way a master animator with Flash. I'm not trying to discourage anyone from becoming Flash artists. But if you decide to buy/rent Flash and make projects, know that you will not start out with full videos, actions, or even fully-drawn characters. Flash takes time and work. It's not easy, but it can be done.
My experience with Flash has given me a whole new respect for the art form and the artists who do it. The time it must take not only to draw the characters, but to properly animate every frame and voice astounds me. I can't believe that many of them are 13.
So for those who are starting, I say, "good luck." If you work hard at it you will eventually make great animations. But using Flash, like may other things, is a process. You will not make a great video your first attempt, but with time, you will be able to.