Legal Question about child support and relinquishing parental rights?

Okay, this is a long story. Basically, my ex's mom had temporary custody of my son from birth. When I got on me feet and was ready to take care of my son, the grandmother fought me for custody. October 2010, I finally got primary custody of my son, but the grandmother still has standard visitation rights. (2nd and 4th weekends, holidays, summer and spring break, etc etc) Rose, the grandmother, never took perry, the father of my son, to court. Only me. So I had to pay child support the whole time as well as driving two hours one way twice a week just to see my son. I faithfully did all that for two years while fighting this custody battle. Perry, my son's father, was never taken to court and never made to pay child support. He got to see Hayden when ever he wanted, which was a lot because he lives in the same town as Rose. Well, now that I have custody, Perry told me that he does not want to go to court, pay child support, or have court ordered parental rights. Perry still gets to see Hayden, my son, whenever Rose has her visitation with Hayden...which is half the time. Well, I was going to go through the texas attorney general to get Perry to pay child support, but come to find out, with paying child support, he gets his own visitation time. (which I am fine with) My question is, when they give him a visitation schedule, will the judge take away my time or the grandmothers time? I dont know if it would be worth it to get Perry to take some responsibility if they are just going to take my time with my son away from me. How does this work. Another question I have is, I am re-married to a wonderful man. We have been married two years. Mike, my husband, is very loving towards my son. They do everything together. I changed my last name to my husbands last name. So now, my husband, my step daughter, and I have the same last name, and my son has my maiden name. I talked to a professional to see if it would be in my sons best interest to keep my last name or to change it to my married last name. She said that Hayden would feel like an outsider to my family by having a different last name than everybody else and that it would be a good idea to change his last name to my married name. Well, come to find out, in order to do the name change for my son, Perry has to agree to it or voluntarily relinquish his rights. Otherwise, I wont be able to do the name change. Perry and Rose have already told me they want Hayden to have Perrys last name. I didnt agree with that because Perry doesnt want to take any responsiblity for his son, not to mention, my son lives with me and he is my son and I want him to have whatever last name I have. (Perry wasnt even at the hospital when Hayden was born. He wanted nothing to do with him. Perry even told his mom not to take my son in and to let CPS take him, Rose did anyways, and I am very grateful for Rose taking Hayden in, despite all the trouble.) They then threatened to take me back to court and etc etc if I tried to change Haydens last name to my name. I think Perry would relinquish his rights but his mom wont let him and if he did anyways, it would create problems between them, so he wont do it. What do I do? I mean really. Perry wants to see Hayden but not take care of him. How is that fair to Hayden? How is that fair to anybody but Perry. I need help with clothes and things like that, but I dont want to have my time taken away from Hayden. Perry does not deserve to get Hayden to have his last name. Am I wrong? Any advise would help. I dont know what to do. Mike, my husband, is way more of a father than Perry is. Mike supports Hayden emotionally, financially, he provides everything for him. Please help. Any suggestions would be awesome. I am so confused and torn on what to do and I have no idea how to even start all this. I dont have the money to keep going back to court, but I make to much to get financial assistance. :(