FMS2 Install,

First: I installed FMS onto my IIS web server. I selected all the default settings. When I rebooted all my websites stopped, and they would not restart. Later I found the problem, it was because FMS was using port 80, and not letting IIS to run. I had to stop the FMS service, so my IIS could start.
What went wrong?
If ever get the above fixed, how can I stream FLV files.

Please Help.

Server :
Flash media Server 2.0
Windows 2003 server web edition OS IIS
Have Cold Fusion 8 running