Welcome to the forum!

Lucid dreaming is definitely a great way to stop nightmares, or even turn them into positive experiences. When you're lucid, you can even ask the dream straight up why you're having the nightmares, and often your subconscious will tell you. In the meantime, if you're looking for help understanding your nightmares, you can always post in either the Dream Interpretation or Nightmares and Recurring Dreams subforums.

And it's totally fine to post your past dreams in your online DJ. You can even back-date them by setting the option "Post On:" to a previous date.

Let us know if you have any other questions, and feel free to stop by the IRC chat.