It is purported that those who see the little girl first have a great ability to see life positively and are able to overcome obstacles easily.
Your Tango explains that those who see the little girl first have a "youthful spirit" and their "special perspective" that gives them the strength not to bow under pressure even when circumstances are difficult.
The skull
If the first thing you saw was the skull, don't panic, it doesn't mean anything sinister or that you are disturbed.
According to Your Tango seeing the skull indicates you have great intellectual power.
You are rather clever and enjoy some seriously deep thinking.
The scenery
Others may have overlooked the girl and the scenery entirely, instead shifting focus to the scenery in the background.
For those who zeroed in on the dark woods it shows that they posses a tendency to trust your "gut instincts".
This is a good quality and following your instincts will lead you in the right direction.