Whatever the answer, we should use the same standards as we use for everything else. Religion is not a privaleged topic so we don't apply different standards. So for example different people gave different political beliefs (the closest analogy IMO) many of which are just blatantly ridiculous or bigoted or idiotic. People might like reading horoscopes and think Kate Middleton is interesting to follow. In fact, almost everyone does or thinks something that I think is pretty stupid. So I don't much know whether I am supposed to "respect" these things or not, but my point here is that I don't "respect" religion more or less than many of these other things.
Incidentally, I don't think most political or religious beliefs are formed through careful objective analysis. They are often more about cultural identifications and the like. Seems hard to really disrespect somebody who is the product - as humans are want to do - of their own culture, even if that culture is more than a bit iffy.
Either way, I certainly don't feel any emotional animosity to people of differing political or religious views than me. Except the folks that think that small tits are acceptable, those are just wrong, I could never respect them.