My wife withholding my children at her mother's house

I am married for 12 years. My wife is an unethical, arrogant, ill-tempered and quarrelsome lady and there is a marital tiff going on between us since October 2012. We have two kids a son aged 9 years and a daughter aged 3.5 years and they both are studying in a nearby school. On 27.03.14 my wife left my home on petty issues with both my kids and went to her mother’s house in Meerut. Till date my wife has not returned to my house. Both my kids have missed their school for almost one and a half month. I have telephoned her on numerous occasions to return back with my kids but she is refusing clearly. She is dictating unreasonable terms and conditions for her return which are unacceptable to me. I want to bring my kids back with me as school is now going to open from 1 July 2014. Earlier, my wife was saying that you can take your kids with you but now she is refusing clearly to give my kids back. My son is willing to return back with me but my wife is threatening him and creating undue influence on him. I don’t want to bring my wife back as she has made my life hell. My wife’s mother’s house is located in a dirty and lower class locality in Meerut and there is lack of amenities at her mother’s house like electricity, water, space etc. unlike my house. My kids are staying there unwillingly. I want to bring my kids with me very immediately and don’t want to follow long procedure of law like divorce proceedings or custody proceeding because these are time and money consuming procedures. What legal and/or social remedy is available to me to bring both my kids back immediately or at least my son who is aged 9 as their school is going to open from 1 July, 2014. Kindly guide.