Some Scooby Doo cast member pulls off the mask of the monster and some random person that appeared in the episode's face is revealed. He then shouts, "And I would have gotten away with it too, if it weren't for you meddling kids"
Refers to the old practice of grading cotton not the highest or lowest quality but the grade in the middle between the best and the worst. Southern collaqualism means fair or ok
The catchphrase that the villians of the television show "Scooby Doo" would utter after being apprehended and unmasked.
"That's right, it was I who committed the quadruple homicide and armed robbery. And I would have gotten away with it too, if it weren't for you meddling kids!"