Need Some Good Advice ASAP

[smcgarry]

What is the name of your state? Texas
As I have said before, I am a Grandmother with joint managing conservatorship of my now 1 yr old Grandchild with her biological parents. We have been to court a few times now and I have had custody since December, 2003. The biological parents have not followed any of the court order and are about to be unemployed. (They keep changing jobs and I can't enforce support withholding until they stay still for a while.)
The father has a criminal background and now has a warrant for his arrest out for traffic tickets.
I actually have a couple of questions and am sorry if I'm not in the right forum for all I need to know.
1. Since the court order has not been followed, that includes visitation rights, and when visitation rights are exercised the baby doesn't want to go and clings to me and when she comes home she is defiant, can I get visitation reduced on those grounds?
2. How long do I have to wait before I can file to legally adopt, and how difficult is it?
Thank you, and sorry this is so long. Please forgive me for being ignorant, but I know nothing and am trying very hard to learn!
Thank you.