I like most of them for different reasons.
Mewtwo strikes Back is good because Ash dies. I like when stuff happens to him, iono why, but it's like he's a puppet XDD;
Pokemon 2000 was good because not only did Ash basically die [XD], but the movie in general was also action filled.
The third one thingi was ok. Nothing to remember.
Pokemon 4ever was cool with Oak and stuff. Ash also passed out XD. They actually had Celebi die, which you may say didn't matter, but it's one of the only times that I've heard the word "die" in Pokemon. I liked that. :<
That Lati@s one was good with the Latios thing. It made me cry when I first watched it.
Deoxys and the umm... what was it? Jirachi! Were good. I didn't love Deoxys since nothing bad happened. Jirachi was cool in how it brought Max's character out, but May's singing voice was unrealistic.
Lucario and the Mystery of Mew was my favorite. Lucario and Myuu are two of my favorite pokemon. Ash and Pikachu's connection was cool too, and the whole "ZOMG LUCARIO AND AARON ANGST" was Womhg yummy. >:3
Manaphy I didn't see that. But I saw the pictures and I like how May cried a lot and how Ash almost drowned, but I wish he did drown and was saved a little later. XDD
Darkrai was ok. Bleh. I don't know. Not too great with angst and such. Boo.
Yeah. I like angst and death in Pokemon. Don't know why, but it just gives more of a realistic twing on stuff. Heheee.... XD