except Pakistan whole world salutes India's secularism and democracy, India is the only country to provide subsidies to Muslims going to mecca, I dont consider Sikh as minority as they are same as Hindus in many practice and Christians are not at all discriminated in our country, They are infact proud Indian Christian and again they mix well in the crowd...
but i think that Muslims somewhat feel isolated , and thats there in every country with Muslims.. they are strongly connected with their religion and thats what stop them to mix with people from other religion, but generally they are not discriminated..!! infact we try to make them not feel left out..
in case of christian, sikh, buddhist people, we can speak anything and touch any volatile topic as we are sure they will not be offended as they are as proud and as Indian as us but i must admit that when it comes to Muslim we have to take extra precautions to not hurt them, I dont know whether evryone will agree with me but generally muslims are reserved but thats not the problem of Indians or India..
Strong attachment to religion is what stop muslims from mixing well with people from other religion but that my personal opinion