The commute from Chickasha to (depending on what part of) Fort Sill will be anywhere from 35-40 minutes. I don't think traffic will be any issue at all, especially since you are coming from the Baltimore/DC area. In fact, there would be NO city in Oklahoma where traffic would be an issue with you and you won't be commuting within city limits at all; most of your drive will be countryside.
For distance questions and such, use
Google Maps. It's a great resource.
As far as the schools in Chickasha, go to
Great Schools - Public and Private School Ratings, Reviews and Parent Community.
I did a search on Chickasha schools and came up with the following. They don't appear to be too bad.
Greatschools.net Search: Chickasha
Good luck and thank your husband for his service and YOUR service as well. Military spouses contribute as much to the welfare of this nation as those who serve directly.
PS. I think Chickasha is probably a pretty safe choice. Small city, relatively low crime, and it does have a hospital (
GRADY MEMORIAL HOSPITAL). Their website is
http://www.gradymem.org/