From what I've read, no, they generally don't get convicted. However, it's still horrible to be accused of murder after being forced to defend oneself, not to mention the potential costs of defending oneself in court.

I seem to recall one incident where the homeowner was charged with striking the burglar/home invader with a cricket bat. I don't know what happened afterwards.

And I'm sure there are exceptions.

I also recall reading somewhere that the only self defense tool legal in England is a personal alarm.