Dealing with non-Muslims

Q: Is it jaaiz to say "jazakallah" to a non-Muslim?

Q: I want to ask that a teacher has a very pious place in our religion (he is like a father), but today my teacher is a sikh. Has he the same place?

Q: Four days ago a Hindu friend of mine was showing me the idol and addressing it as god and asking me like "do you know what this god's name is?" I in my heart I knew that Allah is the only lord and there is no god except Allah but I told him I don't know his name and then he told me it's name and then I said I have heard it in some movies. Was there any kufr in my statement because I did not tell him directly that the idol is not god and when he asked me "what is the name of this god?" I said I don't know. By seeing the scenario it looks like I don't know that god's name (but in my heart I knew Allah is the only god). I usually read the shahdah after every wudu. This happened on Thursday and I started getting doubts about these statements on Monday. So if that was kufr and I have prayed Salaah for four days, should I pray again but I read the shahadah Thursday itself after wudu. Were my salaah valid?

Q: Some Aalims spoke about Mandela's 'Islamic character' in their talks in the Musjid. Please elaborate as to why this is inappropriate.

Q: Is praising a non-Muslim allowed in Islam? And what is the sin of praising a non-Muslim?

Q: I have a disabled 5 year old son who needs to be watched 24/7. I cannot work and muslim organizations can't help me. Can I go to a church for help as some non Muslims are more sympathetic towards disabled children?

Q: Is it allowed to befriend a non-muslim? I have a non-muslim friend. He is a good man and helps me in studies, etc. Should I break friendship with him or not?