Not too long ago I began using the Slackware distribution of Linux. If you don't know what is is it is the oldest maintained distribution of Linux, Since I have been using it I found that I have had the most enjoyable experience since I was using Linux. This distro quickly became the best distribution I have ever used, and this is why.
Simplicity: Slackware is extremely simple. When you install you basically have the system, with the x windows system, and several desktop environments. You can customize everything from the ground up. And it's main user interface is the most natural one the command line. Most things you do in Slackware involve using the command line, this gives the user more control of the system.
Ease of use: Slackware is considered to be hard by many users. But the truth is that it is easy just different then so many of the Linux distributions today. If you are considering trying Slackware, but you afraid because people tell you that it is hard. Try it anyways, and I think you will be pleased. Like I said before Slackware uses the command line a lot, which to me is the fastest user interface in a whole lot of cases. Why should one go through ten different gui screens to do something that can be done with one command?
Speed, and Stability: Slackware is the fastest distribution I have ever used, but it is also the most stable. It has never crashed before even while using the most resource consuming software, and it will still be just about as fast.
Slackware to me is the most stable, secure, and customizable Linux distribution available. Since I have been using it I can see the true potential of my computer. So if you truly want to free yourself, and push your computer farther then ever nothing beats a good Slack. :)