I did something similar with my most recent 4e demo. I was running Raiders of Oakhurst (not reloaded) and I wanted to throw in a skill challenge so the players could get a sense of it as well as the regular combat.
To do so, I had the kobolds taking children from the outlying farms as well as livestock in the most recent set of raids. The PCs entered town and were immediately commissioned to eliminate the kobolds and find the children. A local trapper led them to the caves and begged them to save the children. This led to the initial combat with Ichi-Ichi and the gang roasting something over the fire, but it was too far burnt to identify (though several players "had a bad feeling about this", ala Star Wars). After taking down Ichi-Ichi, Otto-Wombo, and forcing Varkaze to run, the ranger heard muffled crying from the room to the right.
Upon entering the room, they searched it and found several sets of rent, bloody clothing and one terrified, crying girl under a blanket in the alcove to the north. I had them roll initiative (mainly to ensure that everyone got a chance to act before going back around) and announced that anyone that wanted to could enter into the skill challenge. Of note, the player with the ranger opted to stay outside the room and ensure that Varkaze did not return. He actually had more fun playing rear guard and appreciated having the choice.
The rest entered into the skill challenge. The paladin went first and opted for a perception check, making it (1 success). I told him that the girl looked almost hysterical and was trying to pull the blanket back over herself. The cleric went next and tried a heal check, also making it (2 success). He was able to use a Healing Word to take care of most of her physical wounds, but the sheer terror remained. The fighter tried an insight check to see if he could recognize the family, but failed (2 success, 1 failure). I told him that little girl became even more frightened after watching the dwarf eyeing her so carefully. The warlock and wizard opted to do nothing. The paladin, having seen the cleric heal her, tried to do the same. Unfortunately, he failed (2 success, 2 failure). He tried to lay on hands, but she shifted and he ended up grabbing her arm too tightly scaring her even worse. The fighter then tried to use diplomacy to calm her, and was successful (3 success, 2 failure). Then the wizard tried to make a perception check to notice anything, and succeeded (4 success, 2 failure). He noticed that the girl was now glancing between the paladin's holy symbol and his sword. Finally, the warlock tried an insight check to see why that might be and succeeded (5 success, 2 failure). He noticed that most of her wounds looked like they came from the spears the kobolds were carrying, and the short sword had a similar blade (to a small child). The paladin did not know what to do, so he abstained. The cleric tried yet another heal check (I gave a penalty here because there was little more to learn) and failed (5 success, 3 failure). He was not able to do much more than feel her heart racing far too quickly. From the description, they knew that the end was near for the girl one way or another. The wizard stepped up and asked the warlock if he could go. The warlock agreed, and much to my surprise, the wizard used his daily spell to try to save the little girl. He cast Sleep on her. I asked to roll an easy arcana check to not send her over the edge with his chanting and he succeeded easily. The ranger went out to get the trapper, who was ecstatic to see his little girl alive, if unconscious.
They celebrated saving the girl more than any monster kill. They got into to the point where they were deliberating between each other between turns to find a good solution, and seemed very anxious whenever there was a failure.
We finished the demo, which ended in a TPK from the dragon. But they all said that their favorite part of 4e was the skill challenge and that was what they were talking about as they walked out the door.