It's a very tough question when it's narrowed down to just a single year, but I guess I'd have to go for the year Jesus started off his 3-year mission in Palestine too, so as to see what really happened with all that. (This assumes that I would be culturally adapted and able to fit in and understand the language of that time, etc.) It's just a lot more important than all the little personal stuff that's going on in my present lifetime, so that's why. I'd like to know the facts firsthand, rather than a bunch of hearsay and opinion from a variety of individuals who all had various (often differing) political agendas in their minds when they wrote down what's in the New Testament. Early Christianity held a great many different viewpoints about Jesus and was split into many different factions...some of whom eventually won domination over the emerging Christendom...while others were suppressed, wiped out, called "heretics", and most of their ideas were lost to posterity...because most of the books they wrote were deliberately destroyed.

If a different set of early Christian ideas had won out in that power struggle (and they might have), there'd still be a Christian religion, but it would differ in a number of key points of its doctrine and philosophy...and that could have had a profound effect on the development of our whole culture.