A little backround on my life before DH and stepparenting.

I have tried everything imaginable with my son's dad, he lies, he gets out of everything. I'm desperate because I don't want to make a life for my son without him and then when he decides it is fit he can stroll back in.
When my son was little I tried and tried to make him apart of my sons life, and he found more important things (drugs, dating teenage girls, ect.) before my son was born he had a domestic violence charge, interupting a 911 phone call,and 2 possesion charges against him(I am sure there are others.) After he was born he proceeded to get 2 more possesion charges and skipped out on his court date. As you can see he is just a peach of a person.

Now I'm at the point where my spouse loves my son and has been the only father figure in his life, so i went to see if there was a way to get rights removed from my sons dad and put them where I feel they belong with my spouse. So two weeks ago I finally got my sons dad to call me and discussed this with him since he has evaded child support and had not seen my son or had contact with my son in over a year, i told him I would pay for all legal costs and he would not have any more resposabilties for him after thats point, he was pretty okay with the idea and told me he would get ahold of me in a few days and discuss more. I let him know if he decided he did not want to sign his rights away then to contact CS (i have not gotten a dime from him since my son was born) so I did not have to have them chasing me anymore. He said oh yeah I will blah blah blah. In short I have not heard from him since and I am thinking about taking legal action against him to have sole custody/or have his rights stripped and my son could be adopted by my SO.

Before anyone jumps over me I don't want to do this out of spite or anything of the sort. I want my son to have a good male role model and his BD is obviously not fit. I also don't want him to get any sort of visitation with him due to past and present bad choices.
I also don't want my son to feel like its my fault his dad is not around when he gets older.. Or feel like I did not give him a chance to know his dad
Is it right to take him to court for this? My lawyer says I have a chance and he feels confident in the case.. :?