Children who are "reluctant writers" may have dysgraphia or may be visual learners. My son loves to make up stories but hates to write them down. Typing them on the computer helps, but he is very visual and likes to illustrate his stories as he writes them.

For a visual learner, instead of using a word processor for writing, try having your child do their writing in one of the popular greeting card programs (choose one which allows you to make signs, which are essentially a full sheet of paper). That way your child can incorporate graphics, clip art, colors, fonts, and other special effects which will appeal to ther visual senses as they write. We prefer Print Artist, but Print Shop is also popular.