Request... couple a question about mini-movies

Hey everyone! So I just learned how to make mini-movi animations and I can make this: to where it is under 39.1KB to post on threads.
And I am wondering
1. How can I get it on a cool background like this: or something, and
2. keep it under the 39.1KB rule?

And I also have one more question...
When making mini-movies in photoshop/imageready, and you jump to photoshop to adjust the coloring,etc... is there a way to sharpen the animation besides having to click each thumbnail and sharpen individually?
I use Photoshop, Imageready, & ImageGrab, as well as PSP7 and Animation Shop. I've tried searching and stuff but I'm not seeing any that says about the size rule...
Thanks so much in advance!