Loady scrolly function

Hello,

Ok, this is easy I am sure, but I need someone to steer me in the right direction.

I have say 5 buttons that when clicked use Loadmovie to load one of 5 respective jpegs into an empty movieclip on the stage and then makes the loaded jpeg scroll down the page a bit.

I believe that the best way to do this would be by using a function on the main timeline that has instructions to make a jpeg load into the movieclip and then scrolls it.
The buttons themselves only contain a variable that is the corresponding jpeg file name, and then calls the function to make it load etc.
When another button is clicked the scroll is reversed and the process repeated but with a new jpeg (file as set by the button)

Phew!

I could do this by just animating it I guess but I think that this way would keep the file size down quite a bit, am I right or just plain nuts?

Any ideas how to do this?

Thanks.