So your ruling on the Divine Challenge scenario - where the enemy takes damage if he makes an attack that does not target the paladin - is that if the enemy casts Wall of Fire, even if he casts it to pass through the paladin's square, he takes the damage? He's 'made an attack', if we consider any attack power to be an attack, but he hasn't made an attack that targets the paladin.
An area attack's area of effect sets the shape of the attack and the targets it affects.
And the Elemental Maw / Righteous Inferno vs Evasion question? If the initial roll misses, the character takes no damage from the Effect?
Turns out, actually, I think he was spot-on... Wall of Fog is an area attack (it has an Attack Type of Area), but it is not an attack, nor is it an attack power.
Even though these terms are called 'attack types', they apply to utility powers as well as attack powers.
Wall of Fire is an attack (a Wizard Attack Level 9 to be precise). If it targets the Paladin, the enemy is ok. If it does not, he take Divine Challenge damage.
The Paladin is included as a target if he is placed into the Area of Effect of the Attack. Page 271:
An area attack's area of effect sets the shape of the attack and the targets it affects.
Any attack that has an area that includes the Paladin is an attack that targets him and nullifies the damage of Divine Challenge.
This seems crystal clear. Is there a rule that would imply that it works differently?
Now consider Wall of Fire. Area: wall 8 within 10 squares. Target... oops, no target entry.
The area determines which targets the attack effects, but Wall of Fire doesn't affect targets at all.
And indeed, if I cast Wall of Fire so that the paladin's square is affected by the wall, nothing happens to him on my turn. And if someone shifts him two squares away before his turn, nothing happens to him on his turn either. He was never a target of the power, because the power doesn't have targets.
<snip>
Fireball hits multiple targets. Wall of Fire creates an obstacle. Fireball has targets, Wall of Fire doesn't.
-Hyp.
Yup - Target, p57. "If a power directly affects one or more creatures or objects, it has a 'Target' or 'Targets' entry."
Consider Fireball. Area: burst 3 within 20 squares. Target: Each creature in burst.
Now consider Wall of Fire. Area: wall 8 within 10 squares. Target... oops, no target entry.
The area determines which targets the attack effects, but Wall of Fire doesn't affect targets at all.
And indeed, if I cast Wall of Fire so that the paladin's square is affected by the wall, nothing happens to him on my turn. And if someone shifts him two squares away before his turn, nothing happens to him on his turn either. He was never a target of the power, because the power doesn't have targets.
It's true that an area attack's area of effect will determine which targets it affects, but that's only meaningful if the power has targets.
After all, consider p56: "An area power creates an area of effect that can originate in a distant square and hits multiple targets or creates an obstacle."
Fireball hits multiple targets. Wall of Fire creates an obstacle. Fireball has targets, Wall of Fire doesn't.
If you want to use a power against an enemy, the enemy must be within the range of your power, and you have to be able to target the enemy. Many powers allow you to target multiple enemies. Each of these enemies must be an eligible target.
An area attack's area of effect sets the shape of the attack and the targets it affects.
"What is an attack?"
PHB said:Most attack powers that deal damage require you to make an attack roll. The “Attack” entry specifies the kind of attack you make and which of the target’s defenses you check against.
If you want to ask CustServ questions and get proper answers, you have to give them all of the details you have and let them make an informed decision.
Asking piecemeal gets you piecemeal conflicting answers.
Well, my "Talmudic scholar" interpretation is that page 271 is illustrating what it means for something to be an area; fireball and wall of fog are indisputably both area effects.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.