Ubuntu is the easiest to implement and run. It's like the iOS of linux distros. I'm actually on it as I am typing this

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Different distros have a slightly different "feel", but mostly people pick KDE or Gnome based on whatever aesthetic they like. The nice thing about larger/more popular distros are that they are generally 'easier' to use, due to more documentation, and more integration of extras.
So far, I like the visual appear of Ubuntu the most, hence why its the one I picked. I have a debian port on my raspberry pi. When it gets to the terminal commands they're the exact same.
My buddy runs various versions of puppy, red hat, and debian on various systems. My buddy likes the slightly rougher look of his debian/KDE combo on his system, I like the apple-esque look of ubuntu on mine. He has puppy running pretty damn nicely on an ancient military grade laptop running on a P4. Each distro has an ideal purpose, which is whats beautiful about linux. It's such a scalable platform, which is awesome in the day and age of over-proprietization by most major companies.
Big companies have tried to make their software scalable with limited success. However, being open source, linux has this ability to morph into whatever role it is needed for. Where there is a need for a particular implementation of linux, developers and programmers will answer and modify linux to fit. And they do this because it is a labour of love. This is something that will never happen to the same degree with closed source code that is written for the purpose of profit.
Linux is the wild organic vine that grows where the sun shines, whereas iOS/Windows/Etc. is the carefully pruned and manicured apple tree that is grown to produce fruit in the orchard. IMO, distros like Ubuntu are like the tamed vineyards, producing grapes and wine (See what I did there? Apple? Wine?) making it accessible for the masses.
Those are my general thoughts.