My Neighbour Totoro was the first Studio Ghibli film I ever watched, and every time I see it I feel like a little kid again (same feeling I get with a Pixar film), so I'm a little partial to that.
Spirited Away was really gripping as well, and I also enjoyed Ponyo. So I picked those three.
I haven't actually watched Kiki's Delivery Service yet, but seeing as it's a pretty popular choice on here I think I want to!
But I'm surprised you left Grave of the Fireflies out. Very good story, but...so upsetting. ╥﹏╥
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I'm sailing across Spectrum Sea, in my little boat.
The waters of the port were choppy. After I set off, there was a long, massive storm.
Years later, however, the sea calmed. I'm still on tranquil sea, but I'll never reach the Neurotypical Beach.