Dreams, what a subject! Depends on what type of dream it is, I think. I've had some very interesting dreams that actually were a teaching to me, and I've had other dreams that had no meaning at all. It's a bit like our thoughts too, isn't it? So I think as far as dreams go, we have to treat them a bit like our thoughts, and see whether they're just useless or not. This is how I treat my dreams, if they are just a combination of associations then they have no meaning to me, and if I try to figure out the meaning I'm just wasting a lot of time. We feel it's important to see if they're giving us a message or not.
If we wake up from a dream and we're a bit agitated from the dream and it was a difficult dream, then it might be good at that time to actually do Compassion/Lovingkindness to anyone in that dream. If you see the energy behind the dream was fear, try to feel Compassion for the fear. Universalize it, understand how others may be feeling fear at that time in the world. And feeling Compassion for anybody whose life is a bad dream.
As far as trying to interpret every small dream I think that wastes a lot of time for other things that may be of more usefulness to us. Sort of the same as if some thoughts are inspiring and can teach us something, then we be aware of what it means and use it in our life. Some thoughts are useless, you just note them and let them go. Actually when we become meditators we may not even need to try to interpret dreams so much. Because if we're trying to look more deeply into our mind and understand the urges that we have in our waking life, and we start to see what motivates them, especially the eight worldly dhammas and all these other things, then we may not have to interpret our dreams so much, because we're more consciously aware of what is motivating us. We're much more conscious of the memories that are coming up and they're not such a jumble, so that in our normal life we're working to resolve these things.
However if you get very inspiring dreams, they're very useful. Say for instance one dream I had in a retreat was that I was in a car and it was falling over a cliff, and fear arose in the mind at that time, then I said well, everybody has to die, just flow with the feeling. That's what I did in the dream, and I didn't hit the bottom, I woke up! So that can be very inspiring at those times, and you can start to see that your practice is penetrating into your dreams which can be very useful at those times.