B.J. Novak’s directorial debut, in which he also stars, tops the DVD releases for the week of Sept. 20. “Vengeance”: A New York City journalist heads to small-town Texas to investigate a murder for his podcast in this smart social satire. “In ‘Vengeance,’ Novak sets his sights on lampooning the big city media types who go chasing stories in middle America and return with observations from the ‘flyover states’ that are usually condescending, preachy or inauthentic, and in doing so, he finds the humor, and something honest too,” writes Tribune News Service critic Katie Walsh in her review. “‘Ven…