1) Dell laptops aren't all the same and it would be folly to force adult content filtering by default on consumer products as it will likely be adults buying them. I had a Dell laptop a decade ago and it had no such adult filter I needed to disable.
3) A scratch is more likely to result in a disc not being readable than cause a fire. I would expect a fire to be caused by a faulty or damaged battery long before the laser or DVD drive assembly caught fire.

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