I haven't watched Grave of the Fireflies or Barefoot Gen, either. War films kind of get to me, since they're emotinally exhausting by their very nature, and I tend to have a lot of empathy for people. Band of Brothers is all right, because it seems that the violence - horrible as it is - is spaced out over the length of a ten hour series more than it would be in a movie.
Also, the longer running-time lets me get to know the characters better, which can be a bit of a mixed blessing given that this is me we're talking about, but if I can't relate to at least one of the characters then the story tends to bore me.