I find myself explaining pop culture references to my children. All the time. Some of them are understandable, from before they were born. Some of them... I don't know, maybe my children lead a sheltered life?
A recent example is the song, "If I Had $1,000,000" by Barenaked Ladies. I have it on my iPod, and they like it, so we listen to it fairly often. But there's a line about "I'd buy you some art. A Picasso or a Garfunkel." It took several tries to explain who Art Garfunkel was and why this was funny.
This isn't even counting the idiom references. Dial a phone? Sounding like a broken record? Mommy, what's a record? That's guaranteed to make you feel old.