I found this article about an interview with Del Toro and Cuaron and it's very interesting what they say about Harry Potter.
Killing Harry Potter: del Toro and Cuarón
Last week we had the opportunity to sit down (separately) with two great directors, Guillermo Del Toro and Alfonso Cuarón. We had the chance to talk to both directors about the missed opportunities and the finality of Harry Potter.
"There is regret in the sense that I loved the books," admitted Del Toro, who had to turn down an offer to do the third Harry Potter. "By the time they asked me to do the third one, I was coming out of Blade 2. I didn’t want to start doing 2s and 3s and then 4."
Del Toro felt that the first two movies had a much lighter universe than the books: "And I frankly felt the kids were too... healthy for me. Not the type of kids that I’m interested in portraying. So I called the producer and said, 'If you ever wanna kill those kids, I’d be your guy. In the mean time, if they escape their adventures unscathed, I’m not interested. Not because I don’t like the universe. I think the books are brilliantly written and very well researched. I really like that universe.'
Del Toro recommended that his friend Alfonso Cuarón do the project, something Alfanso snubbed at first.
"I never read the books or seen the movies so I was kind of arrogant about it," Cuarón confessed. Del Toro scolded the director over the phone telling him to read the book and call him back. "I called him back and said Man, this is brilliant. And he said 'Yeah, and you have to do it."
And the rest is history, Alfanso filmed the best Harry Potter film in the series, and del Toro went on to direct the best film of 2006: Pan's Labyrinth.
"I think he did a much better job that I would have ever done," admitted del Toro. "Alfonso believes in youth much more than I do. I don’t believe in youth. I believe in the extremes: childhood and old age. Youth is always suspicious to me. I’m 41 and I never went through puberty, so I’m suspicious of that age range."
So if Harry Potter was to be killed in the final book, del Toro said he would be interested in making THAT movie if they would let him.
"I don’t know if she will do it, and I’m almost sure as **** they wouldn’t offer it to me," laughed del Toro. "It was too glib on my part to say it, but I really don’t think that – It’s not exactly a want ad, you know?"
But Will Harry Potter die in the final book?
"I don't know, I had this same conversation with someone the other day about that,' said Cuarón. "In one hand it makes sense, in the other hand - how do you finish Harry Potter if you kill Harry? What is the resolution of the tale? How is she going to finish the seven books and not have an temptation to do an eighth book?" Cuarón asked. "I don't know. And that kind of stuff, I have a really good relationship with JK but I don't mess with that."
Alfanso revealed that JK Rowling called him a few weeks back to congratulate him on Children of Men: "She really loved Children of Men. And we started talking and I said that it was a tough process doing the movie because of the brutality of what you're doing, of what we're picturing. And then she conveyed to me, 'yes, yes, it's been hard for me because when you do writing about hard stuff, you have to sleep with that.' But I don't go into details."
Del Toro thinks some dark times are in Harry's Future: "I’m reading the books as they come out, and I’m enjoying the hell out of them. I actually think it’s heading to a darker place, the entire saga, and I’m really happy about that. I’m really happy about that. I think it’s really coming to a place where they’re really gonna encounter darkness."
"How do you create the ending of a saga which is not a downer if Harry dies?" asked Cuarón. "And this is the only thing I am certain, that whatever she does is going to have an amazing kind of spin at the end. Because she's aware of what Harry Potter is and means in terms of the collective consciousness of humanity. Whatever she will do, I don't think it's going to be careless."
http://www.slashfilm.com/article.php/20061219killingharrypotter