Dreamweaver is an excellent tool for a lot of things.. Especially for CSS..
but when it comes to Database backend design, there\'s one thing i\'ve learned, DW does not like people manipulating its code.
You either have to do everything on your site the DW way, or hand code everything yourself.. because as soon as you try to modify DW\'s code, it\'ll just blow up on you. I\'m not saying don\'t use DW, i\'m just saying.. Be careful. And one tip, if a page does blow up on your after you modify it yourself.. your best bet is to scrap that particular page, and start over..
As for PHP Editors.. the ones I like most, with syntax highlighting and a functions list, and all kinds of other features are:
http://www.ankord.com/phpxedit.html <-- very nice!
http://www.code-genie.com/cgenie.html
Good luck