The disconnection may have occurred because of interference or the distance between devices. There is also the chance that the device was trying to use two different services while it is recommended to use only one. I recommend you disabling or enabling the services as needed from the Services window (double click the Bluetooth icon and the device icon); you may notice the phone is currently using “Play Music”.
I am not sure why the Headset service was unticked but it may help removing the device from the Devices and Printer's list and pairing it again. Usually there is no need to modify those services boxes.
The options to enable or disable WiFi and Bluetooth vary and are specific depending to the computer’s brand and model.
The built-in Windows Help and Support feature in Windows* 7 offers some content regarding Bluetooth. I also added some online articles.
- http://windows.microsoft.com/en-us/windows7/add-a-bluetooth-or-other-wireless-or-network-device-frequently-asked-questions
- http://windows.microsoft.com/en-us/windows-vista/troubleshoot-problems-with-bluetooth-enabled-devices
In regards of the HDMI audio issue I believe you can get it working again after uninstalling and reinstalling the Intel® HD Graphics driver. The Windows* System Restore is a valid option too.