I'm with mom... Have dinner at West Side, maybe House of Blues (you might also check & see if they have a concert on that night - when we were there in May Earth, Wind & Fire were there - now how would that be for a 40 year old man - this 42 year old would like it). Then over to PI & party like there is no tomorrow - don't miss Adventurer's Club.
Or if you prefer the quiter, more romantic, more refined celebration- how about dinner at the California Grill - make the PS for a time so you can watch the fireworks - then since you do have babysitters, well............
I would be a Happy Birthday Boy either way.