The 1800's would be really neat to visit but forget about outhouses think summer and no a/c! I'd also like to be able to go back to the early 60's before Kennedy was assasinated and see more of what it was like back then and then the late 60's and all of the events from that time. But I'd definitely wanna be able to come back to my own life afterwards.
My first choice would be the 1920s - flappers and the jazz age. My second choice would be the 1960s, and I'd want my life to be like an Audrey Hepburn movie.