I did not read the other answers because I am sure they are correct (after a while you see that some people do know what they are talking about).
So why am I posting? To give you some advice (my opinion). I have been using GNU/Linux for a while, not as long as many people (Linux is the kernel, not the OS). Here is what I think may be easiest switching from Winblows to Linux.
1. Pick a desktop environment first.
A desktop environment, just for ease, is the GUI. There are many different DEs. Winblows has only one. Some are pretty, some are not. Some are easy to use and others are not. KDE is pretty and very easy to use, but not for older or slower machines. Then there is XFCE. Ugly and harder to use, but much faster.
Here are some examples:
https://en.wikipedia.org/wiki/Desktop_environment#Gallery
When switching from Winblows to GNU/Linux, I recommend KDE.
2. Get a USB flash drive, and use a program called YUMI.
http://www.pendrivelinux.com/yumi-multiboot-usb-creator/
This allows you to install as many distros as the drive will hold. You can then choose which to boot into on startup. This way you can try them out and see what they are like (they will not make changes to your hdd unless you tell it to). Once you find a distro you like, many will allow you to install it from the usb.
3. Ubuntu is a good distro for beginners, but is uses the Unity DE. Many people do not like it. There are many many distros based on Ubuntu. Kubuntu is Ubuntu with KDE. Xubuntu - ubuntu with XFCE. Lubuntu - ubuntu with LXDE. Mint is based on Ubuntu. PCLinucOS is based on Ubuntu. So try them all out with many different DEs.
4. Have a look at http://distrowatch.com/
They will give a description with a screen shot of many distros. On the right side of the page, a little down, they rank the distros. Root through them and see what you like. and try them out with YUMI.
5. Pick a very popular distro. This way when you have a problem there are many people that can help and many forums that you can look at.
6. Keep at it. Many people will try a distro of Linux and not like it. Most will try to use it like Winblows. They never give themselves a chance to get out of "Winblows mode". It takes a little while to learn, just like it did for you to learn Winblows.
I would like to welcome you to the Linux community.