Linux is a developers dream. The tools at your disposal are quite an impressive arsenal.
Which distro actually does make a difference unless your fond of installing from tarballs. Certain web development IDEs and tools cannot be found in the repositories of certain distros. One of the reasons I got away from Fedora and CentOS is that many of my favorite packages ceased to be maintained in their repositories. This includes some of the more powerful development IDEs.
Ubuntu in my opinion has probably the best repositories when it comes to development IDEs. It is also one of the most user friendly distros though there are some quirks about it I'm not especially happy with and of all the distros the official support forum is the least friendly or useful. You get far better answers to Ubuntu questions on general Linux forums and even on other distro's forums than you can on Ubuntu's official forums.
There are however distro's that are heavily customized for web development and one of those might actually be your best bet. If you wander through distrowatch.com and check out the various distros you'll find quite a few tempting distros.
Whatever distro you choose install both KDE and Gnome libs. Whichever desktop you prefer your going to find apps from both that are by far best of breed not just for Linux but any OS. Only takes a little extra space to install libs for both and gives you so many more first class apps to choose from.
LAMP is the most common web development platform in the world. LAMP standing for Linux Apache, MySQL and PHP. My advice is to create a separate stand alone server. Will save many hours of frustration. If you develop and test on the same machine your prone to paths, dependencies and configurations that are not likely to exist on the server you will deploy upon. So if you use a second box as a test server you find those BEFORE you try to deploy. Saves a ton of aggravation if your test server is as close as possible to the production server in terms of paths, DBs and software installed. Does't take much of a machine to make a LAMP server. Long as you can install Linux on it you can run a LAMP test server that is highly responsive.
There are several good IDEs for MySQL development/management and even CASE tools. You'll also find a wide array of IDEs for PHP development as well as frameworks and toolkits. Many of which are Linux specific. One reason most of the world's web servers run on LAMP. These make RAD development quite simple. However all are not equal and you want to learn PHP from the ground up before jumping into those tools. Same with MySQL. Know SQL, don't rely on SQL generators to create your queries. Some of them create really poorly constructed SQL and more than one web page was made dog slow because of a poorly constructed query here or there.
You won't find anything quite as WYSIWYG as Dreamweaver but their not far off and unlike Dreamweaver you don't spend much time fixing HTML generated by most Linux IDEs. I love Dreamweaver's IDE but hate the code it generates. Every hour I spend in Dreamweaver requires 2 fixing the HTML/PHP/CS/JS that it outputs. Found it just plain easier to use one of the many Linux IDEs instead. Plus Linux tools are free, Dreamweaver costs you an arm and a leg.