Eclipse by itself is a universal platform, starting from which you can create an IDE for just any imaginable purpose using existing building blocks (plug-ins). Sounds exciting, but in fact, we do not want to start building an IDE from scratch, as mutual dependencies between different plug-ins can make this endeavor time and effort consuming.
Instead, I recommend you to download a ready to use package created by Web Tools Platform project, let's call it Eclipse WTP. This package can be downloaded from http://download.eclipse.org/webtools/downloads/ (look for something like "WTP all-in-one package"). You can download either the latest version 2 or the previous version 1.5, they should be equally good for our purposes, but please note that when testing version 2 on Linux, I got some unexpected behavior from it.
Eclipse WTP has quite a number of benefits over the bare-bones Eclipse, including the following:
It has source code editors for different Web-related formats,...