Use that sing-song voice. Some people say it's annoying and stupid, but children do react to it. (Don't have the sources to hand, sorry.)
Offer him choices. Don't say "Would you like a drink?" but say "Do you want milk? Or do you want water?" to encourage him to say stuff.
If he's babbling that's good, you want to encourage any noise making.
About the other stuff: investigate "attachment parenting". Poor attachment in early life can have serious effects. You want to try to fix this.
Really, just spend time loving the child and interacting.
There are some programmes designed to help with poor behaviour. Webster-Stratton is one. It gets some criticism because of the way it's marketed.
It might be worth asking some questions on the parenting stack exchange. I seem to remember some people there did work in this area.