iTunes decides to backup my phone every single bloody time I connect it. There is no way in the current version to change this but the link below shows how. The path was wrong fro me and the correct one is listed beliow. Basically copy and paste the below command into a “Run” box (on Windows 7) and it is deactivated and you can do backups manually or not at all.
C:\Program Files\iTunes\iTunes.exe /setPrefInt AutomaticDeviceBackupsDisabled 1