What sparks true imagination in a story?

While listening to "The Selfish Giant" in class, I can't help but sit there and imagine the story. The details read from this story create a images in my mind. Earlier in class we discussed the phrase "pictures and images fuel stories and art." Personally, I'm not an artist, and I'm not always the most creative person. However, I think it's one thing to hear that phrase and one thing to put that phrase to use.  Throughout the story, you’re introduced to children, a selfish giant and his giant garden. I automatically think of children around age of five, a large guy that looks rough on the outside but a softy on the inside, and a large field full of colorful flowers and fruit. I’m sure everyone pictures this story set up differently, but this is what I believe makes up the story. Reflecting back on the phrase “pictures and images fuel stories and art”, I can understand the meaning. What makes a good story? The ability to create meaning and pictures in your readers mind. How can you do this? Create meaning and pictures in your mind first, then begin writing. The Selfish Giant is just one example of a story that exhibits this phrase. Another famous example is “The Lion, the Witch, and the Wardrobe.” Some of the most well-known books all start with a simple image in your mind. So before you hit a writers block, sit back and just create in your mind a beautiful picture.