Regarding the "start coding" thing, i'd recommend that you start small, and work your way up, if you ever find yourself boggled, or stuck. A platform game involves a number of skills that only a certain experience in coding may bring, mostly on the technical part (correctly drawing to screen, animation, handling the physics of the objects, game logic). This is probably bypassed if you're resorting to one of those game engine types like Game Maker or Multimedia Fusion, i've never used one of them but i think that is their function.
Anyway, a platform game will work well for you if you have the necessary enthusiasm to take it from beginning to completion (which sometimes involves keeping it up through times of absolute lack of enthusiasm, just pushing on to get to a better part of the development process, or to get it done), but if you want to have a steady, solid base, and make sure you don't give up because you got boggled by the large ammount of information needed to do a game of that kind, i'd suggest you start by doing a Pong (the one with the two paddles as both sides of the screen, and the ball going back and forth between them), and then move on to a Tetris, Arcanoid or Minesweeper type game (which aren't as exciting, but will make you advance a great deal).
Graphics wise, i liked the original one better, with the outlines. I'd just prefer to see them not black, but more similar to the color of the object they're surrounding, like an orange around the sun. Also, you could keep the outlines (or colors) of objects on the foreground dark, and the ones on the background lighter. I liked the initial character better too, the black stick man, looked like a bomb or something
The colors look ok to me, nice contrast, altough .Takam's edit had a nicer sky tone, which worked well with the yellow of the sun.
There is a video tutorial by Kazuya Mochu on this site, from a few months ago, that deals with doing platformer backgrounds, you may want to do a search on it.
Good luck with your games!