I can see that to stay competitive in the IT field it would be in my best interest to learn Linux. My question is which flavor of Linux and what is the best way?
- Via the Internet
 
I think you're making the right move. As to which flavor of Linux to start learning, look at what those you know are using. From what I have seen, RedHat is one of the popular distributions in the U.S., and SuSE has a large gathering in Europe. With the acquisition of SuSE by Novell, SuSE may see additional popularity in the U.S. There are other distros such as Mandrake, FreeBSD, etc. Each has its strong points and best places to be used. Once you have learned one distribution, there will be differences in other distributions, but nothing too major.
 
While there are several good books that can help you learn whatever distribution of Linux that you want, the best way for me was to approach it from a project perspective so everything I was learning was directly related to the end goal. Two good projects I can recommend are implementing SpamAssassin and Snort. You will find both on the Web sites of the respective applications and by doing an Internet search for a series of how-to documents. In some cases they will walk you through the installation of the OS used by the author and then the application (I have found both RedHat and OpenBSD used). One thing that I would suggest is use the exact version of the OS mentioned in the document. I found that one application I was looking at, Snort, required different rpms or modules if you were working with Fedora Core 1 vs. Core 2.
 
You may find that you need some help along the way. The first thing I would suggest is take the how-to document you're using very slowly and check off each step as you go, so if you get distracted, you will know where you left off. Check the Web site of the application and note the listserv or reflectors available. Subscribe to some as you start to work on your project. You will find, for the most part, a community of individuals ready to help you on your way. See what books they recommend to help you on the path to learning Linux.