Simple animation for LED signs for a new animator.

I work for a jewelry store, so I need to find a simple to use, free program that will allow me to quickly create and modify videos for our sign outside our store. I don't know if it pertains at all, but I draw cartoons all the time, and I am proficient in CAD software, so a filled interface is not daunting to me. I just want something simple, that I can create videos on in a good amount of time.
Thanks lads.