I just wanted to add a quick thought on the "if I smack my kids they will tolerate smacking from their partners" idea. I find that somewhat illogical. Would you expect your partner to put you on the naughty chair? Give you a time out? Take away your privileges? Absolutely not. We all understand that discipline is for parents and children, and not for husband and wife.
If you abuse your children - hit them in anger, or even give them the "silent treatment" when you are angry at them, etc, - then they might accept that in later relationships, but that is not the same as discipline. A controlled smack on the bum, in private, accompanied by teaching, and an explanation, followed by a hug is not going to be confusing for your child.