About to start my first game of WoW. Just want to confirm my interpretation of the rules: Once a resource(non quest) has been placed, it can only be used as a resource from that point on. In other words, it stays in the resource row for the rest of the game. Is this correct? Looking forward to my first game.

Pretty much right on.

When you place a resource, if it's a quest, you may play it face-up, and fulfill it's completion power at any time afterwards, which turns the quest face-down. If it's not a quest, you must play it face-down, and it is also a resource, but what the card originally was is pretty much inconsequential.

Now if you have to destroy a resource as part of a cost or effect, and then had a way to return that card to your hand, it could obviously be played as normal.