I'm not clear on which part of 'normal' you are hoping for. I'm not sure if you are clear on that either.
There are many degrees of 'normal'
My first thoughts are that you want your children to socialize comfortably. I'm told sports helps kids learn social skills (I wasn't allowed - so this is hearsay). Since they must sit while at the hall, why don't you take them to dance or gymnastics classes once or twice a week? It's physical activity and gets them to meet other kids their own ages.
As they grow older, school will offer a variety of extra-curricular activities. It could be your job to introduce them to these and help them choose which groups they want to be a part of. You can be the parent who drives carpool and helps out. Let school and these activities take priority. If they are too tired in meetings, let them stay home. Maybe the rule in your house is that they are encouraged (??? ick) to go with mom to Sunday meeting but weeknights is up to each child - only if they have their homework done first.
You can find a network of families and friends to provide good 'normal' activities. Let the kids choose if they want to attend the Kingdom Hall.
Many families have one parent who is very active in the 'fun' things and another parent who is more sedate. Many families have parents of different religions. Kids can learn that each person is allowed to make up their own minds on what they want to believe. It can be empowering. You get to be the broad-minded parent. And the fun one.
I could not tell if you are hoping to celebrate all the holidays. Seems to be that you may do well to just be tolerant of what happens at school - the kids can participate on whatever level they feel comfortable. Christmas can become a seasonal event with a Snowman theme that lasts in your house until January 21. Birthday parties may be allowed, too. Before my parents started studying, a jw friend from school came to my party. She even brought a gift. (I was 8).
Course, if I was JW mom in-good-standing, this would probably break my heart to see my young children celebrating holidays... Athletics is one thing, but blatant, devil-worshipping paganism is another.
Sounds like you've got a steep road ahead of you. Good thing you've got an internet connection and JWD is still running strong. You're gonna need the support.
I truly wish you the best. Look forward to hearing how things progress.
-Aude.