Thanks for your personal message; I'll answer here if you don't mind.
First off, I don't think you "migrate a site to Dreamweaver". I am not sure if this is a term confusion, or a misunderstanding on your side, so I'd like to clear that up.
With Dreamweaver you can build sites in many server side languages like PHP, ASP, JSP etc, or create simple static HTML sites. In it's simplest form, Dreamweaver is like Notepad in that it allows you to create text based source files. However, it's much more than that as it allows you to build complex, dynamic, database driven web sites.
The language of your choice largely depends on personal preference, background, production platform, books you may have (or get) and friend's preferences. In your case, PHP seems the way to go.
Beginning Dreamweaver MX 2004 (a great book for learning DW and ASP) has a strong focus towards ASP. The three sites built in the book are created with ASP. The appendices explain how to set up a site with PHP and JSP but there's not as much detail as there is for ASP.
If I understand you correctly, you'd be mostly oriented on the design, right? That is, general layout, XHTML templates and CSS, and leave the PHP to programmers?
Dreamweaver, possible in combination with Fireworks MX 2004 can definitely be used for that kind of task. In fact, IMO it's probably the best tool for that kind of job.
Hope this sheds some light, and feel free to ask any more questions....
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