Devil May Cry

My bad, I've only posted here once before, it's been awhile. I edited it.

I'm very inexperienced with Paint.NET and would like to learn some of the basics of photo editing. First off, the Magic Wand. Currently, I have this image: I would like to remove the empty white background behind it. Can someone give me a step-by-step on this? Please and thanks!

No, it kept on changing the other value to maintain aspect ratio. I just forgot to uncheck the "Maintain Aspect Ratio" box. Oops. Problem solved.

I just recently download this and am currently at a loss on how to change to size of a picture to 256x196 while saving it as a .bmp folder. For instance, the picture I want to change the size of is this: I want to resize it to 256x196 and then save it as a .bmp file (which I know how to make it .bmp in the end). Thanks for your time.