Movie and source files configuration

Hi everyone,

I am a newbie to flash and have my first project.
Wondering how to plan the site before I get started.
It is essentially a portfolio site for a photographer friend.
There are four different galleries with ahout 5-8 images in each.

my question is: would you build this project as one continuous flash movie, or would you treat each gallery, or even each image as an external file with a preloader?

I want to of course keep load on the site server and viewers connection down, sso we don;t suffer any chugging, but wondering for a site such as this where we are dealing with imagery that is less than 480 x 640 would be necessary.