Mine is probably when Ash finally beats Paul in the Sinnoh League. That last part with Infernape against Electivire, was awesome. Especially in the Japanese version, when Type: WILD starts playing. Here's a video of it.

 

http://youtu.be/A2dxgD3RD80

This:

 

 

And That:

 

That's a really hard choice for me

 

I have lots of favorite scenes from anime and listing them here will take forever cuz I can't decide which one is best

Right now, this.

https://www.youtube.com/watch?v=hMyActacNgo

I love Teen Titans...

 

I thought the part where Ash jumps of the Prism Tower to save Pikachu was pretty rad as well.

Naruto spoilers:

 

 

 

Not a fan of this specific upload since they edited music over it that broke the mood, but this moment was so emotional. ;_;

 

 

 

 

And the scene after that, when SAsuke's looking out at the ocean and remembering Itachi.

 

 

And the last one's one I doubt I can put up a video for, since it's really gory, but I'll describe it:

 

 

When Obito sees Kakashi kill Rin, then massacres the entire Mist army in his rage. It was just so different from anything else in the series, it actually scared the crap out of me seeing that happen. It was perfect for showing what pushed Obito to join Madara.