This movie has violence that could scare younger or immature kids. I think someone 9 and up with an average maturity could handle this movie, even if a few scenes might be considered somewhat intense.
There are scenes of romantic suggestion as well as kissing. I would let my very bright 9 year old son watch it with his mother and I present, but not my 7 year old daughter, who wouldn't be interested in this type of movie anyway unless it had a princess or talking butterfly in it, or something like that.
In regard to message and role model, Peter Parker is a teenager who struggles with his emotions due to his parents leaving him and his uncle being murdered. Due to these circumstances, he may come across as another self-absorbed and mildly rebellious typical teenager, motivated by revenge and using his new power as a tool. That's the main message though, using his power responsibly, but the young protagonist must learn it firsthand and makes mistakes along the way. Despite all of that, as Spiderman, you can see that he has a strong sense of justice and ultimately strives to do the right thing in spite of his underdeveloped emotional intelligence and lack of awareness of objectivity, both often associated with kids of his age. With the wisdom and guidance of his kind-hearted grandparents, Peter is an overall good person who tries to do the right thing, and the movie portrays him with great character and good person. Despite some human flaws, P.Parker as Spiderman is portrayed as every bit the hero that has kept his story alive for generations. Sometimes, due to inexperience, mistakes are made but he always learns from them, ultimately becoming a better person on his path to the altruistic and self-sacrificing hero your friendly neighborhood Spiderman is known for.