You can set activities for a Media Player (CD, DVD, Blu-Ray, or video tape), Radio/Music player, which can include devices with hard drives, mp3 players etc. The Media recorder section might control a DVDR or or VCR. A PVR is usually part of a cable box and is controlled in Watch TV mode.
If you have an unusual setup with say, two cable boxes, or a cable box and a media server such as Apple TV you may need two Watch TV activities. This can be done as a Custom activity.