How can I change the color of a scanned png and edit part of it out in illustrator cs6?

The image is in color with a white background. I want to make the image white with a colored background. I want to switch the colors (make image white and background the color of the current image. I also want to cut out (delete) the bottom part of the image. Is it plausible to do in Illustrator cs6 or should I just use photoshop? I want this to look like professional graphic. The image is a png.