I usually dont like rar'ed movies cos they take too much time to unrar and etc, but i finally found a way that can make my life easier and wanted to share it with you in case you are not aware of.
1- Go to this site and download Dziobas Rar Player.
2- Install it.
3- Now you can select any rar file from FILE menu or drag&drop them to watch your rar'ed movie. You can also add subtitles.
PS // This works on a rar files made with store mode which is mostly used by release groups...