My ex-wife hasnt seen her kids in over 4 years let alone call them. She lives a different state as I but not far and I am worried about my children. they dont really want to see her and I was also wondering about her rights since she has basically abandond them?

Her rights are as they were last time they were set by the court, likely during the divorce. If you do not like that custody decree, file a petition for modification of custody with the court. You would need to ensure the ex is properly served and has adequate notice. In the modification, you may seek primary custody with visitation and ask the court to outline the visitation allowed by the mother.