I wouldn't exactly call it the worst finale ever. In spite of some things --- like Dr. Kelso still working as Chief when, just last week, he opted to retire from his job and Dr. Cox has replaced him; or Keith briefly appearing this episode after his bitter break-up with Elliot. I swear, I did stop midway through and thought I was watching an episode from last season.
But whatever was wrong with the sequencing and continuity didn't matter to me because despite what you may have read about this being the worst finale ever, elsewhere --- I loved it. My son loved it. And I would consider this as a classic, definitely. If anything, the episode was very Scrub-esque (c'mon....fantasy? princess, knights on horses, magic potions?).
Directed by Zach Braff, the final episode was narrated by Dr. Cox as a fairy tale story he was telling his son, Jack but with the real story running parallel to the fantasy.
In "My Princess", the Village Idiot, JD, is trying to help the princess, Elliot, thwart an evil monster (which looked like that black smoke from Lost) that had affected her maiden/patient. Dr. Cox played the knight, Percival, who guides the two.
The rest of the cast didn't have a lot to do with the main story but their fairy tale alter egos were purely entertaining. Couples Carla and Turk played one person --- a two-headed sorcerer/res named Turla. The janitor was Giant Janitor and Dr. Kelso was the evil Lord Oslek, with a devil's outfit to match. Even Ted the lawyer had a fairy tale character counterpart in Toadie, Lord Oslek's servant.
This show has seen its last episode on NBC. Zach Braff has confirmed they're shooting Season 8 already, but this will be aired on ABC this fall.
Here's the final two minutes of the season finale: