Last night I dreamt....

I have really vivid dreams. I am sure that if I put as much imagination and effort into writing as I do dreaming, I would be a bestselling novelist!
What is preferable though, waking in a cold sweat from a nightmare but then feeling the relief that it was only a dream, or waking from the perfect dream to the realisation that it was little more than fantasy?
I am lucky that I don't have that many awful dreams these days, although I do dream a lot which probably means my mind finds it difficult to switch off. My dreams are quite often a bit jumbled with people from different times in my life all popping up together at places where they would never in reality meet. I think a dream analyst would have a field day with me...they would most likely deem me a little mad, and probably wouldn't be too far from the truth!
When I was young I went through a phase, as most children do, of having a lot of nightmares, it was horrible. I also used to have these other really weird experiences that were half-dream and half consciousness- in these semi-dreams I would have to perform some impossible task, a recurring one being having to make a fruitcake the size of the house and then eat it (I wonder if the fruitcake was some kind of symbol of my mental state?!). I usually was conscious enough to get to my parents and come out with some drivel like "I can't eat it, it's too big", at which point I usually woke up. All very strange.