Hi
So, what you're trying to create is some sort of simple social network site. Where each one of your visitors would have a page where they could post photos and something like that. Right?
Well, I don't know if you can do this with dreamweaver alone. I think you should look into CMS solutions.
I know that you can do this with Drupal. You can create a website where your visitors can be allowed to create their own blogs, post their images, change templates... But Drupal can take a little to learn and get into.
You may also look into Elgg or LifeType. And I believe you can do the same with Wordpress, especially if you look into this: Wordpress Mu.
I know some CMS can be configured to work in some ways with Dreamweaver (like Drupal or Wordpress) but I never tried this.
Hope I could be of some help.
Sonia