GOODFELLAS - exempt from classifcation...

During jr high and high school - 1997-2002 - it was largely considered uncool to watch anything with a positive vibe or message.  So aside from WARRIORS OF VIRTUE (1997) and a handful of PG-13 comedies, it was violence upon more violence.  It wasn't until after 9/11 that more kid and family friendly options started becoming available...neverminding that little to anything of any artistic value has made its way to theaters this past decade and a half or that R rated movies are more violent and sex-filled than anything that could have come out in the 1980s or 1990s.
But anyway; when I first saw GOODFELLAS in 2001 or 2002 I didn't know why I'd spent 2.5 hrs of my life watching it.  My mom seemed to get it - she said if even half the disregard for one's fellow man depicted in that film is accurate, it's still a chilling truth, or something to that effect.  I rolled my eyes and a few times later found myself racking my brain going "WHAT???!!!!"
  I don't know if GOODFELLAS serves any actual reason for existing.  Did the film benefit society at all?  Was there really ever any controversy over the FBI's take down of the Italian mafia groups?  If there was, I can see how the film has neutralized such controversy, as you rarely hear any badmouthing of the FBI's anti-mafia efforts.  I can't pretend to know anything about it, because until less than 10 years ago, when I was in my mid-20s, I didn't realize that the mafia was a real threat to people in many big cities in the USA.  The idea of "the mafia" always struck me as a cartoon of sorts.  I knew it was real, but it never had anything to do with any facet of my life that I was aware of. 
But anyway; the idea that kids could get their hands on it and be warped for life doesn't apply in this case.  You have to be the polar opposite of a child in order to understand and appreciate the movie.  It IS very slow paced and it's a long movie regardless of that fact.  It's not fast paced and colorful like Oliver Stone's NATURAL BORN KILLERS or many of the action films that Arnold Schwarzenegger starred in from 1984's THE TERMINATOR up 'til his unsuccessful attempt at regaining mainstream and critical acclaim (1999's END OF DAYS) after wowing audiences with his participation in the epically awful BATMAN & ROBIN (1997).  And if you have kids sleeping in the next room, you could consider using headphones, although a lot of name brand TVS don't have a headphone jack (My Seiki 22" LCD does, hehe).
Aside from the fact that GOODFELLAS is "so boring that your kids will fall asleep before they become de-sensitized and its' rallying cry against "the" mafia, the film does have some other positives, but if you haven't the patience to sit through it, you probably won't notice them as they are quite subtle.