This is a personal question that you have to answer yourself, but I will tell you how I react to her. To me, she is evil and scary. She is a Satan figure, so nothing about her is supposed to be good. However, when Edmund first runs into her, he is ovewhelemed by her beauty. She is all white, and has a beautiful sled, is dressed beautifully, and talks very sweetly to Edmund. She gives him the delicious Turkish Delight candy, which he cannot resist. In the Bible, we learn that Satan does not always go around like something scary - like a roaring lion - but he sometimes appears as what he used to be before he was kicked out of heaven, and that is, the angel of light. So the White Witchs is kind of like that - she looks good but she is rotten underneath.
Edmund soon finds out that he cannot resist the temptation of the Turkish Delight. So, like Satan, the White Witch is able to control Edmund. He becomes a slave to his sin. Only Aslan can free him, just like in the Bible, if someone becomes a slave to sin, only Christ can save him.
So to me, the White Witch represents evil, Satan, and sin, and therefore I think she is scary!
What about you?