I am pretty sure I know when I am dreaming, and I only seem to dream when i sleep 2 nights in a row, and/or sleep in late.
Well, I've had experience with waking with no evidence of having dreamed, and then being reminded of the dream by something later in the day. Not often, but occasionaly.
Notable aspects of my dreams?
For a while, I'd always realize I'm dreaming whenever I happen to come across the word 'dream,' such as reading it on a book, or through word association.
Thoughts are always muddled, so that I'd often encountered situations where, although I knew I was dreaming, I was afraid that if I did something stupid ( like jump down a dangerously high ledge, or act a certain way around someone ) , it would somehow effect me
after I wake up. That's always frustrating, when I do wake up, and I realize that I just lost a rare chance to safely jump off of a five-story building.
Among the most consistant phenomena in my dreams is that, although I don't run particularily more slowly atbest, I have to keep my steps at just the right frequency and move in just the right form in order to run faster than a slow jog.
Scenes that I somehow associate with videogames are also common. One prominent example, I had a dream in which I felt I was playing Super Mario 64, except that absolutely nothing about it was actualy like the game, except that everything around me was in bright colors, bland textures, and some of the terrain formations were vaguely reminescent of the level-design style.
I don't dream that I'm not myself, that I know of, nor do I dream in third-person ( although I might feel like the dream is in thirdperson, because I know that the place I'm in is supposed to be so, like the videogame dream I described above ) . On the few occasions that I've bothered, I've been able to see text and words perfectly, and I've never even heard of dreaming in grayscale.
None.