I gave a thought after typing my post that you may as well be running Skype (listen on port 80) and SQL Server reporting services does that too assuming you are Microsoft product lover like I am, but still thought of waiting for your reply to get confirmed.
You dont have to uninstall SQL Server, just go to SQL Server configuration manager, select SQL server services (on left side pane), double click SQL server reporting services and click STOP.
after that, switch to Services tab, and select start mode to Manual.
Other than that, if you have Skype installed, let me know too, i'll pave you way to get rid of its issues too.