Should I dump my boyfriend? I have multiple issues with him. No chemistry,abusive to his son,bad ,boring?

I am re-dating my ex boyfriend from when I was 17. We dated from 17-23yrs old and then I dumped him because he cheated on me and got a girl pregnant. He now has a 12 yr old daughter from that and an 8yr old son by two diff women.The daughter lives w/her mother and he is a single father to the son.The sons mother isnt in the boys life.We are now both 31. He was boring and our was fair back then.I have now grown alot ually and experienced alot in the 6.5yr relationship I had after him.The person I was dating was extremely fun,had great ,intruded me to alot of stuff and made memories w/me. however on the down side he was very controlling and abusive to me so eventually I left him. I met up with my ex this question is about on 1/7/07.He is still boring which didnt bother me at first bec I was just lonely. The thing is though we have no chemistry.I have no feeling around him and our is boring.He is so traditional and predictable in everything. He is really nice to me and is very easy going.The most we have done in the past few yrs is go to dinner,movies and two comedy shows.His mother basically raises his son. She takes and picks him up from school because my boyfriend works a job from 6-5pm.He doesnt even try to adjust his life to fit being a single parent.,He puts the responsiblity on his mother. So when weekends come we have no sitter.Since is is boring to begin with he never has suggestions on things to do w/a kid. We just rent redbox movies every weekend and go out for lunch and /or dinner. most frid and sat we are in the house for the evening by 5 or 7pm!. In my last relationship we hung out late and clubbed and went to museums and bowling, bars etc however as I mentioned had that dark side.Sometimes we go to the wine vineyard which or course is my suggestion and we ususally go to the liquor store .sometimes I would like to go out for drinks but we cant w/a kid.I feel a certain kinda way about his son bec he nor his daughter should be here.They were both a product of his cheating. My boyfriend never sees his daughter,he just pays child support.I have never even met her in 2 yrs now..He is extemely verbally abusive to his son and beats him sometimes. The child is petrified of him and acts like a robot around him.He's a good kid and its sad.I dont have any kids. I just feel like this kid who isnt my responsibilty is too much burden on my life.I don't want to be bothered bec I dont have too. For the past yr he has talked about marriage saying we must belong together after meeting back up w/no communication for 7 yrs.I think it was just concidence ,,personally. He talks about us having kids after marriage and that he wouldnt treat them like he does his son bec he would want them.Thats awful to say about his son and I have told him so. How can he love and treat another child well if he cant do that to the kids on earth now. I've tried to ist him on single father counseling but he just acts interested and never follows through. I try to make it work to now avail.I want to know if I should let him go?