i honestly doubt that the U.N. could end those but the Nations that reside in the U.N. could. This might sound like a stupid point to make but the U.N. mostly is a communication-forum, an effort to have nations talk to each other and to make working together easier. The U.N. might ratify something concerning world hunger or poverty but without the member states doing something about it nothing will happen. The U.N. simply has no power to force something onto nations. That is also why the U.N. will not be able to ban lolis. It is rather a comdenmation, which is also bad.

But yeah, i too see this as a pr-stunt. People are so infatuated with pedophilia-hate that they will turn their brain off at the mention of the word.