Well... this all depends on if we can ignore language barriers (babel fish type translator, perhaps?). I'm going to assume we are ignoring the possibility of creating time paradoxes and the Butterfly Effect theory of time travel, so if we can ignore langauge and culture barriers, I would say Ancient Rome. As for what I would do, well, you know the saying: "When in Rome, do as the Romans do". I would do what the ancient Romans did, at least wha the upper echelon of society would do. I would probably want to stay longer than an hour, but I would definetly go back at the end of it. I couldn't live without modern amenities.