A question has just quite occurred to me about the White Witch. In The Lion, the Witch and the Wardrobe, Jadis is said to have just two powers: Making it winter and the ability to turn others into stone. 

Yet in the Magician's Nephew, I have seen she has many other powers. 

"The Queen let go of his hand and raised her arm. She drew herself up to her full height and stood rigid. Then she said something which they couldn't understand (but it sounded horrid) and made an action
as if she were throwing something towards the doors. And those high and heavy doors trembled for a second as if they were made of silk and then crumbled away till there was nothing left of them but a heap
of dust on the threshold." - The Magician's Nephew 

Also... 

"I had already cast strong spells on the hall where the images of my ancestors sit. And the force of those spells was that I should sleep among them, like an image myself, and need neither food nor fire,
though it were a thousand years, till one came and struck the bell and awoke me."- The Magician's Nephew 

So my question is... 

• Does Jadis have every power she likes? 
• When did she get the power of Winter and why that Power? 

Why did Jadis choose to put Narnia in eternal Winter if she could've done anything else? (as mentioned in The Magician's Nephew)