Big part of my mid teens in the late 90's, I think I didn't see the first one in theaters. I watching R Rated movies at 11 and 12, but often without the direct consent of parents. For theaters, I could sometimes see them, but the (in retrospect) silly chasm between censoring sex vs censoring violence, probably got in the way of me seeing in 6th grade. Everyone talked about it, and saw it on VHS first week.
I vividly remember seeing the 2nd one in theaters, it was quite the cultural moment in 1999, Fat b*stard, and all the sight gags were referenced endlessly. Also, vividly remember seeing the third one, which, to me, was maybe the funniest, because some of the jokes were slightly more sophisticated, and my own sense of humor, honed from SNL had probably sharpened, at 16, from 13. Saw with my adopted family, ten deep, middle row in a packed theater opening weekend.
Look no further to the extent of how influential these movies were, than "Blueprint 2", with Jay crooning "ohhh behave"