OK, you want to learn inner workings? Linux from Scratch, I've heard. Though I went the Gentoo route. I can here the hissing already. The Gentoo manual is extremely simple to follow. Granted it's all CLI to start, but it will give you in depth behind the scenes kind of things to actually appreciate how it all comes together. I by all means used knoppix myself to show others how interesting Linux can be.
Though Gentoo is a very nice place to start. Step-by-step instructions, just start from a Stage 3 load. It's all precompiled binaries, IE not waiting around for hours watching your program being built. They also let you do that if you are into that aspect, which I am not.
Where the easy builds give you the quickest path to a working GUI, my major beef is that when I run into the old ball hardware issue (read Newer hardware) you have to hit that good old command line or at least a text editor and do some real work. New video cards(read XFree), motherboards(read kernel patches), kernel upgrades (read compiling new kernels), those things are worth learning if you are going to invest the time.
There is a ton of information to pick up and it seems intimidating to start with, but you'll get a swollen head when you manage to make EVERYTHING work, and you are gaming on your 5.1 sound output to your home theatre receiver, or watching DVD output to your TV.
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