Yeah, I find the record scratch one to be actually really interesting. Play that sound effect for any kid, even a 12-year-old, and they'll know what it "signifies." Comic reversal of fortune, an abrupt stop, etc.
Ask them where it comes from, or what it means to actually scratch a record, and they'll probably be stumped.
Here's one that's less of a movie cliche, and more of a general cliche (it appears in movies, TV shows, commercials, etc.): Clueless Dad doing anything "domestic." Dad can't cook. Dad doesn't know which is the business end of the mop. Silly Dad, he used the wrong detergent. And so on and so forth. It's crap. Complete, utter crap. Most of the couples I know evenly split domestic duties. Cooking, cleaning, etc. I don't just mean "You cook, I'll clean." I mean they both do everything (although guys still open jars and get rid of dead animals and insects -- especially when they've been called in to dispatch them). And yet, a commercial for mac & cheese will show how it's so easy, even Dad, that braindead man-child who would just as soon burn the house down trying to use the stove, can fix it for the kids when mom is out of town.
It's kind of like the record scratching thing, to me. Everyone "knows" and sort of unconsciously accepts this stuff in popular culture, even if it has less and less to do with reality as the years go by. You know what commercial I'm waiting for? The one where mom's coming home from the office, completely frazzled, and dad's already fixing dinner -- like he does every night.
Actually, when I start thinking about it, there's a lot of "gender norms" that are highly prevalent in pop culture, but which are also obviously out-dated or at least incomplete in their depictions (IE: "Only men are commitment-phobes, and women are always ready to settle down). Some of this is starting to shift, obviously (shows like How I Met Your Mother invert much of this, and I gather films like Bridesmaids do it too), but it's still around.