See post #6
Invite them to (accept) Islam; if they respond to you, accept it from them and desist from fighting against them....If they refuse to accept Islam, demand from them the Jizya. If they agree to pay, accept it from them and hold off your hands. If they refuse to pay the tax, seek Allah's help and fight them."
The choices are conversion, payment of tribute or their destruction.
"Show me just what Mohammed brought that was new, and there you will find things only evil and inhuman, such as his command to spread by the sword the faith he preached." -Manuel II Paleologus