No, close the hospitals. That will kill off the old people. I'm not sure what is ideal health index. 100 is a good guess.
Closing hospitals frees up the workers from hospital staff. Corporations make good profits hospitals don't.
If you are trying to gain levels or if you are trying to boost your country score you will want all indexes higher.
The education index depends on what type of state and CEO corps you want. If you want a lot of high-tech and strategic corporations you need a higher ed index. I'm guessing an education index of 100 would keep an average company like oil or missiles staffed. New graduates replacing retirees and deaths. If you are expanding rapidly or you are converting to high tech levels a higher ed index can be very useful. If your population isn't growing, all your corporations are already at max efficiency, and you are not trying for a high country score then destroying schoo