I have several favorite experiences but here are a few of the top ones...
Final Harry Potter movie, opening night, midnight showing. My sisters, mom and dad all dressed up. One of my sisters had this amazing Trelawny costume, and my dad looked hilarious as Dumbledore.
Return of the King (opening weekend). Mostly because it was such an amazing movie. The entire theater gave it a standing ovation lol
Back to the Future (drive in, last summer). Such a nice summer night, sitting outside with my sisters and their boyfriends, watching one of my favorite movies of all time. The showing was free so we ate overpriced drive-in food. It was perfect.
As for least favorite, I'll throw out two as well!
The Black Phone (fairly recently). Good movie but someone brought like 6 kids to the R rated horror movie and the entire time they literally ran around the theater and yelled. Yes, even in front of the screen. I couldn't believe it.
A drive-in showing of Spirit: Stallion of the Cimarron & Windtalkers. I was like 6 years old and was with my cousins for a week in the summer. Our aunt and uncle took us to this showing. I liked the animated movie of course, but then Windtalkers came on. I was traumatized because I had never seen anything violent like that. I hid in the car after a while.