Best way to build a site with lots of parts?

Sorry for the vague title.

I building a gallery site which has an interface with 20 buttons each of these buttons must link to a diffrent jpeg. What is the best way to construct the site in flash to keep load times down, keep it smooth and enable me to add more more buttons and jpegs easily to the file at a later date.

options I’ve been considering are:
one big timeline with lots of goto and play actions
loading external movingclips
scenes

thanks

Chris