I want to know if you have this text in your journal for the end of the Bleak Falls Barrow quest:
Farengar Secret-Fire, Jarl Balgruuf's court wizard, asked me to retrieve a Dragonstone from Bleak Falls Barrow, a stone tablet that he believes contains a map of ancient dragon burial sites. He hopes this will help him understand how and why dragons are returning to Tamriel. He was pleased when I returned with it, and promised that the Jarl will reward me for my efforts.
And I want to know if Dragon Rising is anywhere in your journal, "completed" or not.
Then, walk completely and totally out of Dragon's Reach (possibly Drachenschrei in your game).
Then, in the console, type this: resetquest MQ104
Now walk back into Dragonsreach and approach Farengar again and see if that triggers it.