Good question about paganism. I'm not sure it's specific enough to be an 'ism' the way Asatru or Red Path or Wicca are. All it means is a religion that isn't one of the 'world religions', I'd say it falls under 'condition of having a minority religion' rather than a belief system. Deism, too; although it says more about the deity believed in, not enough more to qualify as a belief system like you might get if deism were more organized.
I'm not anti-Christian. I'm anti-stupid.