[quote="avemaria2010, post:1, topic:228172"]
is watching r rated movies a sin
Watching violence in movies is in of itself, not sinful. If you enjoy watching violence, there might be an issue, but that's when you have to show discretion.
As for sexual imagery, it is always a problem in movies, since deliberately viewing impure images or video is a gravely wrong act. A few sexual jokes here in there is probably not too much of an issue, but skip over any sex scenes, or sexualized scenes of kissing or other such things.
R doesn't mean you can't watch it. Most of my favorite movies are R rated, even such movies as "The Abyss" which contains zero sexual imagery, but some violence, and a lot of cursing. Don't forget as well, that R rated movies can contain similar levels of violence, and sexual imagery, but one can be easy to get around, and the other, not so much. For instance, "Wanted" vs "The Matrix: Reloaded". They both contain high levels of violence and language, but one (Wanted) has multiple scenes of sexual acts, and sexualized poses by the main character, and the other (TM: Reloaded) has a somewhat sexualized side character, a couple of scenes of impure dress, and one easily skippable sex scene.