looks like your main problem here is the fact you’re using layers. Layers are fine if you know how to make the most of the them, but if you dont they just cause headaches. I would recommend building your site with tables. Much simpler and more cross browser friendly.
are the layers. so you can see by this layer here, its positioning is absolute, to the position of 183px from the top and 388px from the left. This means it will always sit there no matter what size the browser is set to. Generally just a bad idea.
You would be creating these layers with the ‘Draw Layer’ tool. I wouldn’t use that. Do some research into tables.
While tables can be a pain to master, they are very effective in creating a consistant looking site on multiple browsers.
If you’re not using Dreamweaver you must be using Fireworks. I believe you can tell fireworks to contruct your page using tables instead of layers. (but im not sure as i dont export html from fireworks)