One of my first exposures to computing systems was with early home computers: VIC-20, C64, BBC micro and the likes, these where very open systems. Moving on to the 'modern' PC age I found the closed locked down nature of Windows very flustrating. Windows PCs never provided the fun of the early machines.
I don't remember when I first came across Linux, I have copies of distros going back a fair while but for some reason I don't recall ever trying to get any running, may be it was the fear of busting Windows and losing my work and data. In 2007, I went back to university to find out some more stuff. Part of the course was a module on webserver programming and we where introduced to GNU/Linux in the form of fedora. Whoooa what an eyeopener, not only could we look inside, we could alter stuff, in fact we were positively encouraged to alter stuff. Since then I have explored as many distros as I could.
In short, Linux put the fun back into computing.
If your reading this because your looking for reasons how and why to tackle Linux - come on in the waters fine - and theres shed loads of help on the internet.