My dd14 started reading these books in first grade and started part of the way through the series with the Goblet of Fire because the other movies were out before then and she had seen them so she wanted to start with one for which she hadn't seen the movie. She did go back later and read the earlier books.
As I recall, it will probably depend on your personal values and your dd's sensitivity level, but I don't believe that there is anything inappropriate and the characters don't start to get into romantic relationships until the Order of the Phoenix or maybe the Half Blood Prince. The relationships never include sex and only include kissing and jealousy or hurt feelings or teen awkwardness around those they like. No one dies until the Goblet of Fire, but it is a quick death with a wand being pointed at the character and a curse being uttered - nothing bloody or gory. Major characters don't die until the Order of the Phoenix.
Are there specific types of things that you think would be upsetting to her so we can let you know if they'd come into play?
