Just thought I'd say:
I got back from spending 10 days in Cape Town and had absolutely no problems whatsoever. We even visited a township (almost synonymous with crime hotspot) and it was absolutely fine.
The waterfront (where we stayed) is great; cheap, picturesque and safe. South Africa is a beautiful country (everywhere you look is aesthetically delightful) and as long as you avoid the main trouble areas (Jo'Burg, Durban?) you should be alright.
That said I wouldn't want to live there. There's nothing like not having to open a barbed wire framed gate to get in to your home.
As for the debate:
Personally I think the OP's father was perfectly within reason to shoot the intruders, in a city with the highest murder rate in the world I think it's reasonable to assume a 'shoot to kill' policy when armed gunman are in your home. Anyone who says otherwise, in my opinion, is wrong.