It's difficult to see Anthony Hopkins as anyone but Hannibal Lecter.
The Rite is a film inspired by true events which basically means everything is a fabrication except for the smallest plot detail. For this film it was true that a student went to Rome to study to become an exorcist under the leadership of a priest who had expelled many demons.
Michael is the young priest who is full of doubt. He becomes a priest only to get away from his family's funeral home business. When he submits his resignation, his teacher advises him to travel to Rome to study to become an exorcist. After describing his skepticism to his adviser there, he is instructed to apprentice under Father Lucas (Hopkins).
Lucas has unorthodox methods (taking a cell phone call in the middle of an exorcism in one scene) and even wrestles with his own beliefs.
I'm not sure if they advertised this movie as a horror movie but it didn't scare me at all. They put in the typical cat-scream-and-jump at you for a cheap scare and the exorcism scenes are a bit intense.
This was made by the same people who made The Exorcism of Emily Rose so it will have a pro-God theme to it. Many people don't like that. For whatever reason, audiences want their evil but hate it when God and the Church is used in a positive way.
In the end, I thought this movie was interesting - there's a twist some may see coming a mile away - but not worth more than a free rental.