Schnauzer would be the best pick, not a better breed in the world. Bull Terrier is a nice one.....
my wife had a Schnauzer - mini Schnauzer, her name was Britta
she had to leave the dog in latvia when she came over to Ireland - broke her heart, she always wanted a dog so bad when she was a girl when she finally got one she was so happy.
Britta got amazing old as well I think overal 15 years or so, at the end my mother in law who's a nurse put her to sleep at home on the couch and she went easy, I held her head while she gave her the injection - she just complained for a second but it was over real fast - real sad otherwise.
I burried her later in the forrest (same forrest were they shot like a million or so jews but thats beside the point) and the grave is still there.
Schauzers are AWESOME - rat hunting dogs, my wife told me once when she went to the country side to visit her grand dad and Britta would go around the neighborhood with Moppa who was a big mix and the dog of her grand dad - one day they found a rat and moppa tried to kill the rat but he didn't know how, she had the rat killed in a second, bit her in the back and was so proud!!!
Awesome dogs