When you study the world of Islam, you find that there is a lot of diversity. It is not the monolithic faith that people make it out to be. The extreme Islamist side to Islam is a part of that diversity but it is a small part on the fringe. Most Muslims who immigrate to the USA and Canada are moderates who want to adapt to their new homes and countries. This means that they are open to democracy, and learning the ways of the local culture. They want to become good citizens and seek prosperity for their families. In this way they are like you and me.
The second part to this question is demographic. Muslims are only a small percentage of the USA (1%) and Canada (3%) so there is no need to worry about the immediate implementation of Sharia Law. Even in places where Muslims are concentrated, such as Dearborn, Michigan, there is no call to implement Sharia Law. Muslims also value the rights and freedoms that we hold dearly in western societies and they are willing and ready to adapt. Let’s be good neighbors and offer them hospitality rather than fear them.