I think we can take the words "big sleep" literally. It's kinda like sleeping, without waking up. And no you will not dream. That's it.
If i'm wrong and end up as a spirit or angel I'll be laughing my ass off and will be the first to admit I was wrong and afterlife is awesome but I find the chances for that to be more minute then "sleeping really deep".
As for reïncarnation... it kinda boils down to the same thing. The current you wouldn't know that you had a previous life, what you did etc so the current you, in a afterlife would still be dead in a way. If not, then why do we have so few (and in my opinion, none) credible people who recall their previous life(s)?
The Doctor will see you now
Promoting Lesbianism --> 
