Whisper of the Heart is a Studio Ghibli film (they're the same ones who did Spirited Away, Princess Mononoke, Howl's Moving Castle, and such). It's a Japanese animé film, of course.
The genre appears to be normal fiction—not the fantasy some might have come to expect. There is some developing romance. The picture of the cat on the DVD cover might lead one to think it's fantasy (but that's just part of her imagination, from the book she's writing). Although, one should note that The Cat Returns, done by the same studio, is fantasy and it does contain two characters from Whisper of the Heart (the cat Muta and the figurine called the Barron; the Barron isn't said to be alive in this one, though; I should note that they look different in each movie, though; Muta is white in The Cat Returns, and they never call him Moon; I don't think Muta is as big in Whisper of the Heart; the Barron just looks different in ways that are weird to describe).
I've read that this film has scenes from real areas in Japan. I have a friend who lived in Japan for a while, and he says this film really reminded him of it (and that they did a good job with the depiction—subtleties and all).
There isn't any violence or foul language. It's rated G.
The animation is done rather well in this one. It's pretty much like Spirited Away in that regard; maybe a little different. Whatever the case, the animation is nicer (in my mind) than all the other Studio Ghibli films I've seen, besides Spirited Away, and maybe Howl's Moving Castle. I've seen most of them. It's not that the others are bad: it's just that these ones are done very well.
I liked this film a lot. I would rate it highly. It might end a little happily for the tastes of some, or the ending might not be as complex as some would desire. I'm sure most people would like most of the movie, at least, and a lot of people would still like the end.
I watched this film with Japanese audio and English subtitles (actually, I tried out the captions for the hearing impaired—though I think I should watch it again without them, as they tend to put the words to the English audio with those, and thus you see words when the characters aren't saying anything, at times—though it wasn't that bad in this movie: whatever you do, don't try it with Kiki's Delivery Service!)
Some might call this a Hayao Miyazaki film, although he didn't direct it (however, he did the screenplay and the storyboard—and he produced it). Yoshifumi Kondo was the director. This was Yoshifumi Kondo first and only film, for he died at a very young age (47). They say he was expected to take Miyazaki's place.
See the Wikipedia article for more information.