Spit and shake hands as much as you want, brother, but only signature with your private key counts in the end!
Nope. Go ask a lawyer. No matter which party ends up with the asset at the center of a smart contract dispute, that said ownership can still be challenged in a court of law. Smart contracts will not alleviate or nullify this.
Riddle me this: Since you and me never signed which jurisdiction is recognized in case of the dispute, and we may be from different countries, do you really believe jurisdiction of my country has power over you?
Riddle me this: Why or when would I ever go into a smart contract with you, knowing this? Lol
I think that there is a very narrow use case for smart contracts, multi-sigs, ICOs (probably a few more) but as soon as the contract involves something happening in the real world, you need some oracle to give that information back to the contract.
This then becomes a weak point, a point where the outcome of the contract is not determined by the code, but by an external human entering the data into some system. This really negates the reason for having a smart contract, you may as well use the normal legal system, the rules have been honed over 1000's of years and are very good & fair.