An Islamic country where others are free to practice their religions, that is easy: Turkey, Egypt, and Morocco immediately come to mind, as well as Malaysia. Really most Islamic nations have large, well-established, minority religions who have been practicing freely within their boarders.
And you will have to prove that Islam has "destroyed civilizations it has infiltrated", since all of those places have had functioning societies for the last 1600 years. If you mean that invaders have taken political control and influenced the culture, well then I think you are a little confused about what "invading" means. If that is the case then you will have to look at what the U.S. has done to places like Japan (we decided they would be a democracy... then put the people we wanted in power).
And Islam is no more or less violent or peaceful than Christianity. After all, the Christian Bible has the example of God commanding the Israelites to exterminate the Canaanites, then punished them when they failed to kill all of the women, children, and babies. You really can't get more violent than that.