We did a short 2 1/2 day trip last year. It was great! Things we liked in no particular order:
1. Walking down Main Street in the "snow" after the fireworks.
2.The MK Christmas parade.
3. "The Night Before Christmas" performed by Mickey and friends at the theatre in Tomorrowland.
4. Lighting of the tree at Epcot.
5. Candlelight Processional Dinner and Show (works like Fantasmic Dining Package with preferred seating for the show).
6. Country Bear Jamboree Christmas Show.
We did not see the Osborne Lights. The kids outvoted me and wanted to spend the last evening at MK. Guess I'll have to go back for the Holidays another year!