I'd visit the near future, close enough that someone might want to talk to Larry Niven and can figure out the language; distant enough to get me decent medical techniques and a ticket to the Moon. ↗
I grew up watching a lot of the coverage of the early U.S. space program, all the way back starting with Mercury and then through Gemini and Apollo and of course going to the moon as the main part of the Apollo program. ↗
If we don't do it, somebody else will. The Chinese, the Europeans and the Japanese all have the goal of going to the moon. Certainly we don't want to wake up and see that they have a base there before we do. ↗