Jedi: I actually said it's the newer movies that are worse. Re-read it, please.
As for my favorite Pokemon Movie, without a doubt, Pokemon: The Power of One (Pokemon 2000 in US). In all truth, I do download the original with English Subs of these after I've seen the one in the US to compare the two. Without a doubt, this comparison shows how much better the Japanese version is when compared to the 4Kids Dub. The 4Kids Dub was good, but the original Japanese just rocked in comparison.
For one thing, in the original, they don't say that it all depends on Ash Ketchum. Rather that a mystery trainer will be the one to save the day. This alone made the storyline a lot better.
On top of this, the little love moments between Ash and Misty in this movie are a lot more cemented. The words used just made the moments more meaningful. I can't remember the dialogue right now, but I do remember it being better. (Oh, and yes, I am a Pokeshipper. (Ash & Misty Love Supporter.

))
I also like the moral of how one person can make such a difference in the world. It just seems to really work for this movie.
The action sequences were also quite good. This was before 3D Animation started causing problems. (Which might be one reason I hated the Deoxys one so much. Simply not doing good enough with 3D Animation.) It's still done in 2D and looks terrific.

In all truth, a great movie and the best of them all. I really can't find a better Pokemon movie than this one.

So to me, Pokemon: The Power of One. The best of the best! :^.^: