Neuromyelitis optica (also known as Devic's disease), see other post from this week, is completely unrelated to ALS
The vast majority (95%) of ALS is not familial. Of the familial cases, we only know the genetic cause in about 20% of these cases. A family history of one, if you have no symptoms, is more suggestive that your fathers case was not familial. If other family members were affected the chance for it being familial ALS would be increased.
I would not worry about this re starting a family. This advice cannot take the place of formal genetic counselling if you wish to pursue this.