On parasite, I'm not entirely sure but it'll probably count as a zombie dog summon and scale with it's level. Not sure what happens if you don't have any points in ZD but it may be a prereq to parasite anyway.
On screenshot, that would be Tristram, not sure whether it's in New or Old Trist though. The guy in the upper left is "Mr. Meatwagon" and the knight is the quest giver who sends you into the cathedral in the '08 Blizzcon demo.
Edit: diablowiki.net says the picture was of the New Tristram starting point.
Links to the two NPC's