Non-technical, no break, stable: Linux Mint.
Regarding Manjaro, maybe try the Plasma version. I have several friends/relatives on it for the last few years and never have to fix problems for them. And these are not technical people.
Manjaro is not breaking it self. You are and you have to learn to prevent that. Going with some immutable is not going to teach you much.
From Wikipedia, the free encyclopedia
Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
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