LORELAI: Don’t even get me started on your Prince Charming crush, OK? At least my obsessions are alive. You have a thing for a cartoon.
DEAN: Ooh, Prince Charming, huh?
RORY: It was a long time ago. And not the Cinderella one, the Sleeping Beauty one.
Prince Charming is the generic name for the royal male love interest in a fairy tale. Rory tells Dean that her crush was on the prince in the 1959 animated Walt Disney film Sleeping Beauty, whose name is Prince Phillip (it’s the one in Cinderella whose name actually is Prince Charming). Sleeping Beauty was the #2 movie of 1959 and is today considered one of the best animated films ever made, although it was so expensive to make that the Disney studio posted a financial loss that year.
Sleeping Beauty has had several re-releases. It was re-released in theatres in March 1986, when Rory was 17 months old. Although Rory could have been taken to the cinema to see it, it was also released on video that year, and Lorelai (or the grandparents) could have bought it for her. Her crush on the prince could go right back to babyhood, and if they owned the video she might have watched it for years as a toddler and little girl.
Sleeping Beauty was next re-released in 1995, when Rory was aged ten or eleven. It is also possible that this was when she developed her crush on the prince. To me this makes more sense, as she was on the cusp of puberty and more likely to be thinking about boys in a romantic way.
Prince Phillip does very vaguely resemble Dean – or at least a cartoon version of Dean wouldn’t look completely unlike Prince Phillip. The fact that Rory liked the prince because he could dance is a foreshadowing of what is soon to come between her and Dean.