Haha, I just read the chat bubbles between those two guys at the top of the first image. I think you're all over the place though, I see perspective, anatomy, body dynamics, realism and toon. You may be overloading yourself.

If you want to start 2D from "scratch", then you may want to find a spherical object, plop it down under a lamp, find a comfy seat and start drawing what you see. Then try a box and cone (a real world example is best but if that's too much then pop open Maya) and if you can find a cylindrical shape (I dunno like one of those big candles) that would be good too.

I didn't really understand it when my dad tried to tell me when I was a kid, but pretty much everything around us is based on these shapes, just like when you want to model something in 3D, you break it down and choose a primitive that will be the base. Keep at it, the only thing that can really get in your way is laziness (and I speak from experience!) :p