Need help animating

This is my first animation: http://www.youtube.com/watch?v=TEfCy68L3-I
The thing is, once I Fu**** up I can’t go back an redo my animation on the editor window. I am still trying to find out where to learn that. I also learned how to make the floor not to traspass the light.
Here is what I need to know, is there a way to use multiple cameras for rendering?
I know I can add a camera while animating and see the progress from differnt angles, but I want different angles y a rendered animation. I already did all the animation of another sphere, but i do not want to push the RENDER button until i know how to do the camera thing.
Where can I find a tutorial for such a task? If you say Google please say the key word, since I do not know english very well, i do not know how to find it.
Thank you.

check here for the camera change tutorial.

If you need any type of help in animation then i suggest you that visit w3schools.com it is the best site where from you can come to know about many things.