This would depend on the type of past time travel. If it's the type that could erase my existence or put even more psychotic apes in charge of the world then nowhere.
If it's the type that the alterations have no real effect on my present but creates a parallel present then there are loads of places I would like to go.
My first stop would be to 2008 to prevent the screw ups that led to my fathers death.
2005: I might have a chance to save my moms life.
1996: To stop my high school GF from being raped. Hopefully this would also be far enough back that the tumor that killed her can be safely removed. I would also make sure my neighbor stays home with his mother instead of leaving for the weekend, so he can be with her when she passes away.
1985: Just so I can visit my self and my family at that point in time. I would want my mom and dad to see how there kid turned out. I would tell my mom and dad that if they don't change what they are doing to there body they won't ever get to see any grandchildren. I would give my grandfather a big hug and tell him how great he was.
About 30 AD maybe a bit less: I would want to see if Jesus was even a real person.
About 50 million years ago: To see terror birds.
I would also want to visit each period the dinosaurs existed in, 100 Ma, 180 Ma, and 225 Ma.
I would also like to go back to around 542 Ma to see the start of the Cambrian explosion.
3.46 billion years: to see just how life got started on this planet.
