The Case For Linux
It just so happens that there is. Linus Torvalds wanted to create a version of the Unix operating system that would work on standard, everyday computers. What he came up with is Linux. It is available in many different versions- Redhat, Mandrake, SuSE, Debian, Fedora and more, many of which can be acquired for free.
In general Linux is stable and relatively easy to use, but it's sometimes hard to change to something you're not as used to.
Linux For Non-Geeks
If you are looking for a detailed, uber-geek, inside out understanding of Linux there are more appropriate books than this one. Grant does an excellent job of accomplishing his goal though- introducing Linux to the uninitiated and sharing enough knowledge for someone to effectively use the operating system without becoming a certified expert in it.
Grant walks the reader through installing and configuring the Fedora Linux that comes on CD with the book. He provides clear, understandable, step-by-step instructions to help you delve into the world of Linux. The book is project-based and teaches the reader how to do most common tasks in Linux.
The only caveat would be that it is Fedora-centric. The book focuses on the version of Linux it comes with, but for the intended audience and goal I think this serves the purpose well. If you want to see what Linux is about, check out Linux For Non-Geeks.