I've just started Linux for Dummies (Richard Blum, 10th edition, 2020). It seems like exactly what I wanted. It is funny and easy to read, yet seems comprehensive - it covers all six options for running Linux on a PC. It has whole sections on desktop environments and covers xfce, Gnome, KDE Plasma, Mate, Cinnamon etc. I immediately feel like this will explain a lot more than the book I reviewed recently (Linux in Easy Steps by Mike McGrath, 2021, 7th edition).
So far: I highly recommend Linux for Dummies to new Linux users!
Later: I'm near the end now. It is still good and covers a lot. There are a fair few typos - all minor, though I'm surprised no one proofreads the whole book before publication. I also got quite lost in later sections. The content is good, it just doesn't explain enough. For example, pp363-4 cover creating a script file. But it doesn't tell you where to save it. Then it assumed you haven't already put it in a folder with other commands, and tells you to enter a relative path of ./ - but of course, that won't work unless you saved the script into a specific folder, which the book doesn't mention. Then it points out you won't have permissions to run the file, without explaining why Linux would not let me run a file I created. Pp367-8 include a script, and says the echo line exists to "output a blank line", yet the example output doesn't have any blank lines, leaving a beginner scratching their head. Small things, but easily fixed with more careful consideration of a new user trying to follow complex instructions.