By Gregg Shapiro

Contributing writer

“Kurt Cobain: About A Son”—AJ Schnack’s non-traditional doc about non-traditional rock star Kurt Cobain is informative and effective. Based on interviews that music journalist Michael Azerrad conducted with Cobain while researching his book “Come As You Are: The Story of Nirvana,” we get to hear Cobain’s story in his own words. Of course, the interviews were audio-taped, so a majority of the visual components of the film are comprised of images of the locales (Aberdeen, Olympia and Seattle, Washington), the local people who populate the cities and towns, still photographs from clubs and concerts and more. Nirvana band-members Chris (a.k.a. Krist) Novoselic and Dave Grohl appear in still photos, as does Cobain’s widow Courtney Love.

As for the subject himself, his visage serves as more of a coda to the movie. The real essence and energy comes from Cobain’s voice describing his early years. From feeling like an “alien baby” adopted by humans, who had what he described as a happy childhood, with a loving and supportive mother and physically abusive father until he turned eight. At nine, when he became a manic-depressive, Cobain took refuge in music, running down the battery in his father’s van while listening to an 8-track of Queen’s “New of the World,” for example. Even as his world crumbled when his parents divorced, music was a source of comfort and also an outlet for creative expression. The combination of constant physical pain from scoliosis and ongoing stomach issues also figured in his personal development, leading him to drug experimentation and use.

Cobain’s outsider status was probably cemented as early as high school when he befriended a gay classmate, leading others to assume that he was also gay, thereby leading to getting beaten up regularly. Cobain said that he was “proud of being gay,” even though he wasn’t. From there we follow him on his course to becoming a “certified self-proclaimed punk rocker” in the “Peyton Place utopia” of Olympia, then on to Seattle and superstardom. The sad but true end of the story makes all of this, in Cobain’s own voice, all the more tragic. DVD bonus features include the featurette “The Voices Behind ‘About a Son,’” director Schnack’s selected scene commentary and “On Location: Scouting Video to Scene Comparison.”

“American Gangster” (Universal)—“Inspired by a true story,” Ridley Scott’s modern epic strives to be an underworld alternative to “The Godfather” or even “Scarface” and almost succeeds, with minor fashion inconsistencies preventing it from achieving its goal. Beginning in late 1960s Harlem, an aging crime boss named Bumpy (Clarence Williams III) passes on both his knowledge and experience, and ultimately his empire, to his driver Frank Lucas (Denzel Washington). Frank assumes the role and the power and soon ascends to mind-boggling levels of power and wealth, primarily by dealing high-grade heroin on the streets of New York.

Meanwhile, New Jersey cop Richie Roberts attends law school at night, with dreams of moving from the prosecutor’s office and becoming a defense attorney. To make matters worse, he is in the midst of an ugly divorce from wife Laurie (Carla Gugino). Roberts’ reputation for being too honest (he turns in a large sum of money he finds in a car during a bust) earns him attention from some highly placed people and he is put in charge of the undercover unit known as the Essex County Narcotics Squad. Soon Richie is on Frank’s trail, leading to a climax in which the men come face to face for an unforgettable showdown. The two-disc unrated extended edition of “American Gangster” contains both the original theatrical version and the unrated extended version on the first disc, while the second disc includes deleted scenes, an alternate opening and much more.