I'd be Vanellope Von Schweetz from Wreck-it-Ralph!
I actually would love to cosplay loads of things and wouldn't be able to chose, however this is the only actually planned, but only the leggings have been worked on. A super tall friend of mine will be Ralph while my short self will be Vanellope, how cute! This would be my first real cosplay, as I don't count other experiences too much.
I've re-designed her outfit a bit for this cosplay, to make it both more flattering to my shape and more comfortable to wear overall, especially as I overheat easily. Vanellope has rosy cheeks and I won't need make-up for it, I have apple cheeks, I glow red right away :P
Here's a few other characters I'd like to do, but just to name a few and not in order.