If you want to remember waking up slowly can help yes, but the main trick is, is to try and recall what happened in the dream shortly after awakening.
Some people even have dream diaries
It really depends, sometimes i know its my subconcious dealing with stuff that bothers me / is going on in my life.
Other times its really hard to find a connection to whats going on / my subconcious could b dealing with.
I personally like to believe in parallel universes, and that during dreams one can catch a glimpse.
That is when its not currently about a drect subject in my life.
As said, very interesting topic ^^