There are several Mormon Ads that work well:

• Take It Personally (Sacrament)
• Take Out The Trash
• No Man Can Serve Two Masters (orchestra leaders)
• The Best Exercise Of All for toning, building and shaping up! (Prayer)

On the video "What Is Real?" toward the end is a young adult woman bearing her testimony in Sacrament Meeting, and as she does a young father watches the fears of his daughter growing up turn into hope.

I plan to add: As this young adult woman testified, the gift of the Holy Ghost is something you carry inside yourself. Not only will you want to focus on what you think and believe, you'll also want to be worthy of having the gift of the Holy Ghost to be with you. This will help you want to live in a way that when others see you, they'll see His, capitol H, influence in your life as you carry the Holy Ghost with you.

This isn't something that you are showy with or self-righteous. But it is something you need to be congruent with.  You all know people who carry the Holy Ghost with them and you want to be with them. You trust them, you know they will be there to help you.

Because you are promised every Sunday when you take the Sacrament, to have His spirit to be with you. So you can keep the spirit above the sand and grime of the world.  Then tie in the sand/washer/magnet object lesson that was shown at the beginning of the lesson: You can't always control what you see or hear, but if you keep your (metal washer) pure thoughts on the surface and (have magnet near the washers) close to the Holy Ghost, (pour sand over them) you can still stay above it. It is easier to have the help of the spirit when worthy thoughts are on the surface where the Holy Ghost can help you, rather than buried three feet under the sand.

Also,  I found a clip in the "Book of Mormon Video Presentation For Youth and Adult Gospel Doctrine Classes". It is available at the Distribution Center, some LDS Bookstores, and possibly in your ward library. Presentation #4, "Can You Imagine"

"A young man is placed in a courtroom and asked several penetrating questions from Alma 5.  The theme of pure and worthy thoughts is the basis of this video. It is cleverly portrayed with bits of humor here and there. A young man is put on trial by himself, and he is also the judge. It makes the clear point that we are responsible for our own thoughts and actions, and to work on having clean thoughts now. It is about seven minutes long.

Another idea I saw last week on Center Street while watching BYUTV. Mike Cottom(?) asked the teens to play a counting game. In teams of two people, he wanted to see which team member could be first in correctly counting the total number of fingers each of them displayed. Then facing each other, he had them put their hands behind their backs and pull them in front holding up any number of fingers. (It's played kind of like Rock, Scissors, Paper, only you count)

It was funny to see the kids heads bob up and down as they first counted their own fingers and then their teammates fingers. After doing this a couple of times, the teens caught on that if they knew how many fingers they had themselves, then they simply needed to add the other teem members fingers and shout out the total.

The point was to be successful, we first concentrate on ourselves and then we can concentrate on others. Be concerned about your own self-talk, personal thoughts, your own focus and then look to others, etc, etc.