These are my favorite problems - the ones people hate but seem resigned to living with; almost as if it's a simple fact of life. When you come in with a solution, they'll be skeptical at first, but you'll know quickly whether or not you're on a great solution for them.
Do you suggest asking people directly what are there most pressing problems helps? Or do you think it is better to observe people struggling with something and then propose a solution and have them evaluate it.