BBB - I am so sorry things are so bad. It doesn't sound to me like you're the one who should be making all the efforts - he needs to change, because if things are as you describe them then apart from financially he is just another drain on family life - he gives f* all.
My DH is quite bad with the phone/computer but it's with work because he's self employed - he doesn't play games (what adult with a job and young kids has time for that?) - The way you describe him, not caring about appearance - being very into his own things, not understanding others emotional needs etc. - do you think he could be a bit Aspergers?
Anyway you don't need my armchair psychiatry - just please know that my heart goes out to you, it is awful feeling like you're making all the running and banging your head against a brick wall.
Remember whatever happens now is going to be better for you and the children because the options are either a). he changes or b). he goes.