Betsy, Muslims have always encouraged conversion. No one has ever been prevented from converting.
This deals with the issue of the tax you mention, which was imposed by the conquering Islamists upon the residents of occupied lands who refused to convert. It also deals with your request for evidence that Islam promotes violence.
//Fight those who do not believe in Allah, nor in the latter day, nor do they prohibit what Allah and His Apostle have prohibited, nor follow the religion of truth, out of those who have been given the Book, until they pay the tax in acknowledgment of superiority and they are in a state of subjection [Quran 9:29]//
There is more which, as well as commanding the faithful not to befriend the infidel, goes into rather more gruesome detail. Separating heads from shoulders, cutting off fingertips…. I'm sure you get the picture.
Just a word of caution. The most likely people to take Islamic literature out of context are Islamic scholars and apologists who make every effort to promote Islam as the religion of peace. Don't be fooled. It is not.
I read your posts and know immediately that your reading matter is designed to encourage unwarranted empathy towards Islam. If I may I would like to suggest you read something that comes from an alternative source. I highly recommend 'The End of Faith Religion, Terror and the Future of Reason' by Sam Harris, and his 'Letter to a Christian Nation' - which is actually a missive to all those of religion. Richard Dawkins says 'Read Sam Harris and wake up'.
Since Khandro's thread is currently almost off the front page of 'News', I'll post another in 'Religion & Spirituality' with a link to this one. From the way this thread has gone R&S is a more appropriate place to continue this discussion - that's if anyone is interested in continuing it. Perhaps I'll see you there?