This is not an easy answer. Easy answer is yes, but how can someone say such a thing about murder or rape? Those ideas do not deserve respect. This question is not really specific enough to get a solid answer. If you're speaking about religious ideas that do not hurt others or are practiced willingly by its participants, then yes. Those all deserve respect. No one has the right to tell someone else how to live and disrespect what they believe. You may disagree and even discuss, but in the end, you should accept and respect. The world would be a better place if more people understood this.
If you mean is there such a thing as a bad idea, then, no...those ideas do not deserve respect. If someone is hurting someone else or violating the rights of others by practicing their ideas, then they are not respecting and in turn, do not deserve it.