Mini movies / ImageReady

I use PS7/Image Ready, and I can't find a tutorial that really explains the basics of making a mini movie with only screencaps. I've been making a 100x100 icon and pasting each cropped frame into separate copies of the 100x100 background... I know this can't be the right way to do it (??) because that only allows me five or six frames before I hit 40k.

So basically, I'm lost. How do you paste frames into ONE background? Is there a tutorial out there somewhere I haven't found, preferably one that goes step by step with lots of pictures for us who are IR-challenged? :) I ONLY have screencaps, no actual movie files.

Thanks.