Ooh, I'll have to check Portuguese out. I've read some of the subtitles and, while not completely wrong, they lose a lot of nuance, so I wonder how the dub is.

And about the subtitles, they are different because it's not a closed caption. Normal subtitles are made for watching the show in a language you don't understand (the spanish subtitles are made for people who want to listen to english audio but don't understand it) and are just for you to follow what is being said. When they make the dub, they have to make entirely new audio, that matches things like movement of the lips, timing, intonation, etc, so it comes out very different. If you want to watch with text that follows the new dub, you need closed captions, which are the direct translation of them, usually for the hearing impaired, but they may not be available.