I am reading "The Hobbit" to my 6 year old son right now. He loves it and as a special treat, we will watch the movie version when we are done.
I read most days for 25 minutes to him. I have a policy of reading real literature books and not those graded "read to me" books because I want to instill a love of good books in my child in the little time that I have to read to him everyday. I too ask a lot of comprehension questions throughout the read aloud time and am surprised when some of the complex sentence structures in these books and the unusual language (to my child) is within his grasp. I also mix in qustions like what he might have done if such a thing had happened to him and could he imagine the dark and dreary night where the characters were plodding through the forest etc and ask him to describe his responses with finer detail.
Before this, some of our more fun read alouds were Dr Dolittle (the original version) and Winnie the Pooh series.
So, go for it and you might find yourself enjoying them as much as your child!