These types of stories are called "myths" and all the myths of a nation collected are called the mythology. Famous examples of mythologies are Greek Mythology (gods such as Zeus, Hercules, and similar), and Egyptian Mythology (gods such as Osiris, Anubis, and similar).
Grunge is like hard rock and punk, although I'm not a fan. Oasis is more along the lines of "Britpop" or rock, but I wouldn't say grunge. Oasis would be your best pick for the second half of your question.
"Tank Man" and "A Man on the Moon" Are some images that come to my mind when I think about powerful images.
Yes, modern performers have the freedom to interpret music of the past in ways that the original composers may not have intended. Our earth has evolved and in turn so have our society and people. The original composers of music like classical music, had a disadvantage because they were only able to write about what was happening and what they thought might happen in the future. There are other kinds of music that we misinterpret because we were not living in those times. This gives modern performers and original composers a disadvantage but modern composers are able to do research about what was going on during that time. This will help them to understand what the songs are about and how to convey them when performing.
