I noticed on the newest version of the Dalek Mod, that there is a model of the 12th Doctor (Peter Capaldi) running with one arm pointed outwards or something. The skin looks really nice on the model, so I'm wondering if I could download it and use it as my Minecraft skin. 

Oh, that wouldn't work well for a Minecraft skin then.

Am I allowed to use the model for an image to be posted on a website?

Yeah that's fine, just credit it if you use it anywhere, i'll let sub get you the file

Awesome, thanks guys.