All, thanks for the tips. We did Valparaiso/Vina del mar as a day trip. Valparaiso was much more interesting than Vina, though I don't know that the trip was worth the drive.

We then did 3.5 days in Bolivia. That was a trip! A few highlights:

--Airport at 15,000 feet and the takeoff.
--Renting a car and getting arrested for driving in the city on a day when our license plate ending was prohibited.
--driving down the death road (plus the 15000 to 3000 foot elevation change)
--taking our car onto a delapidated barge to cross lake Titicaca.
--views at the lake

Had a great time, but renting a car there is not for the feint of heart!!