My personal experience with Linux operating systems has been six years of running Ubuntu on old computers that have cost me nothing. Three or four year old machines outdated by the armaments race and built in obsolescence being given away. Recently, I splashed out and rebuilt two machines, cheaply. I have one machine that is office type stuff and Video and the other which is my Juke Box, music and radio. I am running Ubuntu Studio on both PCs, a distribution that is relatively light which has the relatively light Xde desktop that is not too RAM hungry. In the current Ubuntu distributions there are two families of desktop, the light Xde and the more complex Kde desktop, which has more "eye candy" and uses more Ram! I think that there is an interesting "happy medium" in Ubuntu, it is sufficiently large to have a lot of people working on it which leads to a consistent product. There are a lot of small distributions that can have innovative ideas, which if the core programmers move on risk collapsing. As all of this is open source, the good ideas can circulate freely and are available for the common good. Most off the Linux world is free and doesn't cost anything to the non commercial user. Linux is free in that it can be used and modified by all, it is not free like a free beer, if you was to work on something specific you can pay for the development of your product.
At the moment I have one machine running really well, and the other I have a material hardware compatibility problem, not a Ubuntu problem, I have to update the Bios!
The only thing that is difficult for a beginner is that you have to be able to go into the Bios to set the startup to the CD/DVD player or the USB device that has the system to be installed. A Linux distribution burnt to a CD or DVD is the easiest way to start, once you have a system running, you can use the "Start up disk creator" in the system menu to make a thumb drive or USB disk to install future systems from. If you follow the instructions, it is relatively easy to install a distribution of Linux, extremely similar to a Mac installation. I have never installed Windows on anything, so I don't know how it compares.
Regards, Matthew