You Found A Time Machine, You Get One Trip: Forward or Back?
Much to your surprise, when you come home from work or school, sitting in front of your door is a time machine. No one's around and you don't know where it came from, but it's there all right. And attached to its door is a nicely lettered card with detailed instructions on how to operate it.
The key piece of information is that you get one round trip ride. You can stay as long you like, but once you come back, that's it.
Let's not nitpick about what's possible according to science and physics or Back to the Future. Even if you run smack into your past or future self in broad daylight, there will be no repercussions. But you can also travel beyond the limits of your own lifespan.
Note that everything gets reset when you go back to the present, so don't worry about Butterfly Effect-ing the end of the universe inadvertently. Also, don't worry about leaping into the future and indavertently jumping into the harsh vacuum of space because Earth got blown up by an asteroid. Your one-time-use disposable time machine won't let you do that. This is a no-risk trip.
You have one chance at this: do you go back to witness an event in history or experience the past, or do you boldly head into the unknown of the future?