When I first tried linux I was worried, as you, about not being able to get used to it. For this reason I installed it in dual boot with Windows on my laptop. I never looked back: after a few weeks, I erased my windows partition in favour of a full linux install; then, I installed linux even on my home desktop, which is used by my parents.
So, to answer about "easy learning to use it", I'd say YES. And consider that I am not a computer science student or so; in fact, I was (and I am) a pretty unexperienced user. Start with a simple distribution (Ubuntu, Linux Mint, Mandriva), it will make your learning curve very gradual. You can start by burning a live cd (https://help.ubuntu.com/community/LiveCD
) and trying it.
About security: in my experience, linux is a very secure OS. Basically, the only way you can get malware is voluntarily installing it. Since linux distributions have repositories (or repos, i.e. trusted sources for software), if you install software from the repos and if you keep your password secret, you are safe. A GNU/Linux OS doesn't get infected easily as a Windows one. I read once that, on average, a Windows computer gets infected, by simply being connected on the internet, in 12 minutes. Well, a linux OS doesen't get infected at all
I am very happy to use gnu/linux. I love it. Linux promotes a conscious and responsible use of your OS; it makes you understand how your OS works.