Ah, I see.
Kiki's Delivery Service is my personal favorite.
Ponyo! Ponyo! Little fishy in the sea!
Howl's Moving Castle and Spirited away are also great movies visually and through the story.
My Neighbours the Yamada's is the best movie, because they are all dicks.
Howl's Moving Castle is my favourite, followed by The Cat Returns. Spirited Away makes up my top three, and Whisper of The Heart and Ponyo are also very enjoyable.
I personally didn't like Mononoke either, nor Kiki's Delivery Service. Grave of The Fireflies didn't impress me either. I've not seen the rest.
To-to-ro!! My daughters' favorite movie of all time. Up there for me too.
Single best character of all time. Also, best creature-as-a-vehicle of all time.
CATBUS!
Howl's Moving Castle is my personal favorite, with the usual suspects (Kiki's, Spirited, Mononoke, etc.) rounding it out. Haven't seen a film that I didn't like at all, but many of them don't come close to the top 7 or so.
I first saw Princess Mononoke when I was 9 or 10 and I remember it disturbing me quite a bit. Not in the way a child would be after watching a horror flick, something much deeper. I grew to appreciate it even more after watching it years later and understanding the themes the film was trying to get across.
That said, it isn't the first film you should watch. Spirited Away is also excellent and a much better choice.
Lots of people saying Mononoke should not be your first foray into Ghibli. I'd tend to agree as while it's a fantastic film I would pick something "lighter" to start from. Totoro is classic. Lots of love for Spirited Away as well.
Howl's moving castle is probably my favorite, if only because I love the wizard Howl.
I would disagree that the quality has been going down lately. Maybe we're older and whimsy is hard. Most of the recent stuff hasn't even been directed by Hayao Miyazaki and though the films fly under the Studio Ghibli banner, the directors all have their own styles.
As for stuff coming out, keep your eyes open for both 2013's "Kaguya Hime" and this year's "When Marnie Was There."
Kaguya Hime follows the classic Japanese "Bamboo Cutter" folktale. The story is fairly simplistic, as is the story it is based on, but the art direction in the film is astounding and on that merit alone it almost wriggles its way to the top of my favorites list.
"When Marnie was There," iirc, is the first film without Miyazaki's name anywhere on it. You can definitely tell, but that doesn't make it a bad film. The storytelling is still top-notch.
And finally, how has no one thrown out the FIGHTER PILOT ACE PIG Porco Rosso? Very fun film.
I started with Mononokehime and loved it. It even has Sokka from Avatar in it.