It always saddens me when otherwise very good Christians speak against Islam. I know it comes from a place of ignorance. Those who practice Islam are people who find their roots in Abraham, just like Jews and Christians. Vatican II's Declaration on the Relation of the Church to Non-Christian Religions makes the following statement:
The Church has also a high regard for the Muslims. They worship God, who is one, living, and subsistent, merciful and almighty, the Creator of heaven and earth, who has also spoken to humanity. They endeavor to submit themselves without reserve to the hidden decrees of God, just as Abraham submitted himself to God's plan, to whose faith Muslims eagerly link their own.
Although not acknowledging him as God, they venerate Jesus as his prophet; his virgin Mother they also honor, and even at times devoutly invoke. Further, they await the day of judgment and the reward of God following the resurrection of the dead. For this they highly esteem an upright life and worship God, especially by prayer, alms-deeds and fasting.
St. Anthony's Messenger dedicated their September 2011 issue to Catholic / Muslim relations. I found the following two articles especially informative:
10 Things to Know About Islam
Franciscans and Muslims: Eight Centuries of Seeking God