Harry, definitely. True, his parents aren't human veggetables, but they are dead. He also has Voldemort after him, the Ministry hated him for awhile there, Umbridge made his life flamen' heck, and all that jazz. Poor dude, I'll give it to him though, he's carried it all admirably, I'd've gone berzerk, killed Umbridge and been sentenced to Azkaban for the next ten years.
Neville's gone through a lot, but nothing half as serious as Harry.