Child Custody

Hi, I have been divorced for over 5 years now and I got an ex-party divorce as my husband did not come to fight the case. I have a 10 year old son now and he was 1.5 years when we separated and my husband has not payed me anything till now for him or his maintenance or education, nor has visited the child. I am remarried now and we are all living very happily. I wanted to change his fathers name and his school told me that I need to get adoption papers signed by the ex husband. Initially he agreed and now is asking harassing me for money to sign the papers....He is remarried as well now I dont want any money from him, but want to take his name out of the records as he has not played any role in his life and my current husband is playing the role of a real father now. Kindly let me know the best way to deal with this issue. 1. Should I file for a new case again? and on what grounds? What are my chances on winning? 2. If he dosent sign, then can I ask him for maintenance for the child, as he is money minded and will do whatever it takes to avoid it? I am working as well and doing well 3. Will my son have rights over my ex husbands property in future? Its about 9 years of separation and he hardly has any contact with the child, nor did he ask for visiting in the court... Please help.................