That's the first problem for the Magic Wand - You must manually select all similar colour patches yourself, which defeats the purpose of doing it manually.
-Renegade
again, in my ancient version of photoshop:
Contigious selected = select adjacent pixels of same colour (or similar colour - depending on the "tolerance")
Contigious
deselected= select pixels of same colour (etc.) throughout the image
No idea how to count them though...
and,
as per Ath's post above, I dont really understand the request in the context of the example given...