Hi,
In addition to what Laila has said, i would like to add a few things.
Islam is surely a peaceful religion. Its the media and some other people including some illiterate Muslims who have portrayed a negative image of Islam and Muslims. I would highly recommend you to watch a video called "Media and Islam: War or Peace" by Dr. Zakir Naik. You can easily find its torrents on the internet. I think it is also on YouTube. Watch it with understanding and unbiased. It will surely answer your question and more.
There is another video called "Misconceptions about Islam" by Dr. Zakir Naik. Watch it after watching the previous video i mentioned.
Hope this helps.
-Anonymous