My old Operating System was, like most people, Windows XP. I tried to switch over a lot of times, but I always came back when I had a problem with Linux.
I made it thanks to a few things:

• A friend of me helped me with all the problems and gave a lot of tips about what to do and how to install programs. (Don’t try to compile every program yourself, use your distribution’s package manager)
• My Windows installation was broken, it crashed every time I did something special (For example, when I typed double backslash or right-clicked on a shortcut) Instead of reinstalling Windows XP, I installed Linux. I couldn’t use Windows for daily work because it was broken.
• Instead of Dual-booting Linux and Windows for those Windows-only applications (they are always there), I now use a virtual machine running under Linux.

I’ve been using Linux for more than 6 months now.