What drawing software would you recommend for a beginner?

I would like to try my hand at drawing online. I would like a program that has manageable layering and can smooth out lines a bit, mostly because I will be drawing with a mouse, and I won't have as much control over it as a normal pencil.

I'd love it if it was a one-time purchase, can move from one computer to another without a second purchase(mine may die soon, so not two computers at the same time), and if I enjoy using it I can later invest in a drawing tablet.

I would like a low-priced one, but I just don't know the options besides photoshop and other high-end art software which are way out of my price range for beginning a hobby.

My favorite medium is pencil and paper, and I will likely be using blending a lot, as well as comic/manga style if that helps.