S.P.
We went on Friday. Although my kids are older - even my 11 year old son enjoyed it. I think it's one of the best movies I've seen in a long time. I read some reviews that thought it was a little "dark" - but aren't most Disney movies somehow dark? What about Malificent in Sleeping Beauty or the Octopus in Little Mermaid?
I would take him - you'll both have a great time.