The first sentence, "On one miserable morning, I loaded my kids into the car" is the better choice as it is more commonly used and conveys the intended meaning more accurately. The difference between "loaded" and "moved" in this context is that "loaded" specifically refers to putting the kids into the car, whereas "moved" could refer to any type of movement, such as physically carrying them or moving them from one place to another. Therefore, "loaded" is the more precise verb to use in this sentence, as it conveys the idea that the speaker is getting the kids ready for a car trip.

1 is great. 2 isn’t used.

The first example achieves the intended purpose very effectively. As a native speaker of English, I have heard "loaded" used in that context often even though it's in reference to children. In both examples, loaded and moved are used as verbs. In English, the word "loaded" is used as the task of bearing a load, often kind of burdensome. "Moved" is often used to indicate changing position from one place to another. You set the scene beautifully as "On one miserable morning" and then "loaded" the children. In terms of creative writing, I can visualize the scene. Nice . . . That's effective writing!