I haven't read any DC comics before, but started reading The new 52 series. I've tried various families such as Batman, Green Lantern, Green Lantern Corps, Red Lanterns, Green Lantern - New Guardians, Superman, Action Comics, Justice League and many others.
Whatever family I read, it seems that they are not really the first ever comic of that series. For example Hal Jordan got sacked from Green lanterns in the Green Lantern #1, the Blackest night already happened, Bruce Wayne is already batman and fought Joker and many such incidents.
So my question is where should I look if I want to read about the origins or start of the series? Do I need to read the complete Post-Crisis (Dunno when it started, 1985?) to understand the origin or is there any list of pre new 52 comic which are required to be read to understand the current continuity?