What should I do about my disobidient sheltie

He is four years old, and he is a purebread sheltie. He is shy of people that he doesn't know, except he is great with kids. I took him for a walk up in the bush last week and i was trespassing on my neighbour's fourwheeling trail. Whenever he heard a squirrle he would chase it but if i called him he would come back. He was good until the end, there was the trail leading right down to the house. He ran down the trail, and i called him and he looked back, and i started walking down a different trail but he just walked to my neighbour's house, and soon after my dog and my neighbour's dog got in a fight. he just didn't even listen to me! I was so mad, he ran back to the house and he didn't even stop. He sat on the porch and i spanked him and locked him in the bathroom. And also, its like he listens but chooses not to do what i tell him too. Most of the time when i call him he comes to me, but sometime he doesn't. When i tell him to go on the couch, sometimes he will just lie down. advice?

Shelties are very intelligent dogs and do learn very quickly. He's obviously figured out that he doesn't want to come to you when he does something 'wrong' because he is going to get hit or locked away. Shelties do tend to be rather sensitive to such things and is is very easy to loose their trust by raising a hand to them.

I DO NOT under any circumstances recommend using a shock collar with any sheltie--it is very unlikely that they will respond and will be more likely to loose more trust in you. In addition, shelties are also very stubborn (as I'm sure you have figured out by now) and don't really respond to electric fence barriers--they often don't mind taking the first shock to get out but will often refuse to take the second shock to reenter the property (also these make your pet vulnerable to other animals that might come on your property and attack your pet).