I think that's far too long a time period for a successful trip. Good heavens, think of all the little things that go wrong during a brief 8 month trip to Mars, for instance.

It's far more likely that fundamental breakthroughs in physics will allow for the possibility of interstellar travel in say, the next 100 or 200 years (just a wild guess)

NASA site on interstellar travel

One possible way to travel to a star is to bring the star closer via space-time manipulation. Unfortunately
the amount of energy required to create wormholes is enormous and this idea is just science fiction at this point in time. But then again, walking on Luna was just science fiction once, too.

Worm Hole transportation