As you said that you had doing engineering so if you have interest in Technical then go for M.Tech and if you have interest in Management then doing MBA is better for you all depends only on your interest

Here are some of the best Colleges of MBA:

Indian Institute of Management, Bangalore
Indian Institute of Management, Ahmedabad
Indian Institute of Management, Calcutta
Department of Management Studies, Indian Institute of Technology, Delhi
Department of Management Studies, Indian Institute of Technology, Madras
Indian Institute of Management, Lucknow
XLRI – Xavier School of Management, Jamshedpur
Indian Institute of Management, Kozhikode
Indian Institute of Technology, Roorkee
Indian Institute of Management, Indore
Vinod Gupta School of Management, Indian Institute of Technology, Kharagpur
Faculty of Management Studies, University of Delhi, Delhi
National Institute of Industrial Engineering, Mumbai
Shailesh J Mehta School of Management, Indian Institute of Technology, Bombay
Management Development Institute, Gurgaon
SP Jain Institute of Management and Research, Mumbai
Indian Institute of Technology, Kanpur
Rajiv Gandhi Indian Institute of Management, Shillong
Indian Institute of Foreign Trade, Delhi
Department of Management Studies, Indian Institute of Science, Bangalore
Indian Institute of Management, Rohtak
Jamnalal Bajaj Institute of Management Studies, Mumbai
Indian Institute of Management, Raipur
TA Pai Management Institute, Manipal
Great Lakes Institute of Management, Chennai
Institute of Management Technology, Ghaziabad
Indian Institute of Management, Tiruchirapalli
Indian Institute of Management, Ranchi
Xavier Institute of Management, Bhubaneswar

Some top M.Tech Colleges in India are:
IIT Delhi
IIT Kharagpur
IIT Roorkee
IIT Kanpur
IIT Madras
IIT Hyderabad
IIT Gandhinagar
IIT Guwahati
IIT Bhubaneswar
IIT Patna
IIT Rajasthan
Indian School of Mines (ISM) Dhanbad
Institute of Technology-Banaras Hindu University (IT-BHU)
Indian Institute of Information Technology - Allahabad (IIIT Allahabad)
IIIT Hyderabad
National Institute of Technology (NIT) Delhi
National Institute of Technology (NIT) Trichy
College of Engineering - Pune (COEP)
Vellore Institute of Technology (VIT) – Vellore