I followed someone's advice in here (I don't remember which Dr. Who fan it was), and watched Blink, Fear Her, Army of Ghosts, Doomsday, and then went straight to Time of Angels and Flesh and Stone.

I think I'm going to have to do some more research with the backstory, but is the man River Song is going to kill someday The Doctor himself? Or is it just future storyline stuff and I shouldn't pay attention to it yet?