Dear Sairam, its a general perception that both M.A and M.Sc psychology are way different. The truth is that while everything like the scope, course, duration, syllabus remains the same, the only difference is that MA is Master in Arts so ideally people from Arts background can opt for MA. And M.Sc is opted by students of Science. It can be anyway. There is no rule as which stream should be opted by whom. What should matter is the college or University that you want to pursue this course from. There are few universities which offer Masters in Psychology. They are:

IGNOU

Dr. Ambedkar Open University

Acharya Nagarjuna University

University of Madras

Annamali University

Karnataka State Open University. 

I completed my Masters in Psychology from Acharya Nagarjuna University so I know that it is one of the best in the country.