Snapedom

Yeah, I always thought that was very strange, too. I think that's one reason many people find Harry a weird character and/or are made uncomfortable by him. He just doesn't act normal. Nearly everybody has some curiosity about their families. If, as you point out, the circumstances in which they were raised were very negative, that gives them a very strong motivation to find something positive to counteract the bad things they heard and experienced. Particularly after finding out his parents were war heroes who died saving him, you'd think Harry'd be thrilled to know everything he could about them. He could go on a "quest within a quest" to learn his history.

Now, I realize that Rowling didn't want to reveal too much about his parents because she was holding back Big Revelations to spring on the reader in future books. The easiest way to keep the reader from finding out things was to not allow her characters to ask questions she didn't want answered at that point in the story. But it makes for a distorted main character and constitutes lazy writing, IMO.