Are the nouns "End" and "Ending" interchangeable?

Solution 1:

I wouldn't use them with complete interchangeability. I'd say that an ending is the final step in a chronological sequence, while an end is an extremity of a physical or abstract thing. It might be reasonable to say that the ending of a story is also an end, in that it is an extremity of the chronological line that the story follows.

Solution 2:

Ending is most frequently a reference to a period or space immediately before the terminus, and it normally refers to a creative work. One would rarely hear, "the ending of the road", but one can hear both, "the end of the book" and "the ending of the book."

For that matter, when one says, "I did not like the ending of the book," they are most likely referring to specific plot elements which happened just as they were about to finish reading the book, as opposed to if they say, "I did not like the end of the book," which would mean that they did not like the way the book progressed to completion.

To try to use both:

I did not like the end of the Harry Potter series: I think that Rowling did not manage to hold together the plot well and the preaching about love was trite. That said, I found the ending to be satisfactory: I liked seeing Harry as an adult with a child named {{spoiler}}.