I'm an Eclipse guy. When it comes to HTML/code, I've always been a "hands on" kind of guy—wanting complete control over the code. However, I've just recently needed to use DreamWeaver on a project. While I've toiled around w/DreamWeaver in the past, I've never used it extensively.
One of the things I needed to do was to was compare two versions of a file. I was trying to track down a display issue in the HTML. Eclipse has a nice compare built-in, but DreamWeaver doesn't come with any native compare function. It does however allow you to use an external tool for comparing files.
I found that PrestoSoft's ExamDiff (a free visual compare tool) works great w/DreamWeaver. You can buy the professional version for $35, but the free version has all the basics you probably need.