>>27175781First Movie. It was a decent movie even by non-anime movie standards. Mewtwo made sense as a villain, and the scenery was fucking amazing. Ash's "death" still gets tears from grown men who hate Ash.
Heroes was good, but boring. It is by far the comfiest movie, however.
2000 was great when it came out, but aged poorly as Lugia became less revolutionary.
Honestly, the Hoopa movie was actually pretty good. The plot was beyond garbage, but it had good action scenes. The Keldeo movie is in a similar boat.
The Manaphy or Diancie movies were probably the worst, with the Celebi one just behinf them.