Hi there,
My husband and I both worked full time (still do) when our children were born and the only thing that got him to step up and help out around the house was that I was just too darn tired for sex after teaching high school all day and dealing with the children and house. It was a very interesting epiphany for him when I told him that if he wanted me "rested" for "fun and games" then he better start giving me a chance to rest.
That said, part-time work is still work, just as shift work is still work. Since you both work, house and children responsibilities should be divided up. My husband, despite working 12 hour days, would clean the kitchen and bathe the children each evening. We alternated who got if the children fussed during the night (rare, except in case of illness). He was also very good about being available for me to go out with girlfriends (usually only once a month).
Now that the boys are teenagers, we're still splitting all the responsibilities. Only now, it's who takes what kid to what activity! <g>
The computer is a problem for my husband, too. I've been trying to solve that one for the last 20 years, so I have no real advice on that point. Your husband will learn, as mine has, that you reap what you sow. It was hearing my sons tell him that they weren't interested in my husband joining our fun family activities because "you're always more interested in your computer than us" for my husband to get the idea. Sadly, my sons were 14 and 10 when that happened...a lot of lost time.
My husband and I communicate very well. He might get defensive, but if I take the time to tell him, calmly and rationally, what I think is wrong, he generally listens and finds solutions that work for both of us. From your post, I'm not sure your husband is up to that. In our 20 years of marriage, I've also come to realize that my husband acts just the way his father does. That's really great in a lot of ways; not so great in others. Again, from your post, I think that's what you're seeing, too.
Is this enough of a "problem" for you two to consider counseling? I think the answer lies in how long are you willing to be comfortably unhappy in this situation. Since divorce is not a consideration, the only other thing I can offer is to just do the best you can, live your life without him and never, ever, ever make excuses for him to his children. Let them come to their own conclusions about his behavior. It might take a decade, like it did with my husband, but he may wake up and smell the coffee before he ruins his relationship with his kids.
Good luck, R.. I think you're going to need it.