Trademarks only protect against use of a name in trade, e.g. as the name of a company, product, or service. Additionally, a trademark has a scope of a particular industry that the trademark owner registers it in, which is usually just their area of business. For instance, Cadillac is a registered trademark of two different companies -- one makes automobiles, the other makes dog food. There's no likelihood of confusion, so they don't infringe each other.
Some famous names like Coca Cola and Nintendo enjoy protection over all industries, though.
A personal name is not used in trade, unless they name a company after themselves, as in Steve's Ice Cream (founded by Steve Herrell) or McDonald's (the original location was owned by Richard and Maurice McDonald).
So unless little Nintendo Jones decides to name his business or product Nintendo, he has little to fear from the game company. But if he gets caught in a public sex scandal, I doubt they would have any legal case against him, even if it causes the company some embarassment because people mistakenly think he's associated with them.