It will be hundreds, perhaps thousands of years before mankind will travel to other stars unless some kind of faster than light travel becomes possible.
One or a few ships would never make it. It would have to be a journey of an entire civilization, one large enough and with the resources and technology to endure a journey lasting thousands of years. And it would only make sense to take such a journey when the resources of this solar system have been exhausted. When the Oort Cloud has been exhausted, its civilization might have the ability and the motive to make such a journey. And such a civilization will have little use for habitable planets, they will be looking for systems with lots of asteroids and other low-gravity resources.