Swipe right from Start Screen, choose Tiles, click "clear personal information from my tiles"
What if you select favorites and then shuffle? Does it change anything?
When I go to Photos & Camera, the only options I have are Camera settings, Auto Upload, and Apps. There is nothing for Photos or Tiles.
Go into the photos hub, then tap the "..." at the bottom and choose "settings"
From there, you have:-
* "Start Tile shows" (choices for - all photos, favourite photos, single photo)
* "Shuffle now"