The second one, more is going on and it has more of a funny feel to it. Remember to add ears to Sonic, he looks a bit odd without them. Good job so far, looking forward to more.
Oh, and if you're using Paint, don't use the fill tool after drawing with the brush. The brush tool is anti-aliased, and doesn't work well with the fill tool (thus creating the little white bits). Use the pencil tool instead.