I highly recommend the tour to the Islas Ballestas. There are many animals there. I do however recommend that you skip the separate tour to the Reserva de Nacional de Paracas. According to my guidebooks, I was supposed to see flamingos and sea lions (which I did see hanging out on the Islas Ballestas), but since the earthquake in 2007, the flamingos and the sea lions that used to hang out on the tourist end of the Reserve have since moved far away from where the tourists go. Needless to say, I did not see any animals when I toured the Reserve and I found the tour a little boring.
Do not under any circumstances follow the advice of a taxi driver when choosing a hotel. He will drive you to a hotel that will give him a tip for delivering clients.
The hotel will almost certainly be in an unsafe part of town. Stick to your choice of hotel and ignore his 'wise' advice.
This problem is so acute that the tourist authorities are giving leaflets about this in the buses bound for Pisco (or they were in 2005).
To get to Pisco, you usually take the Pan American Highway. It runs along the coast line between the sea and the uninhabited dry desert on the other side. The sea is cold, so there is often fog that might hamper visibility. Big rocks could fall from the steep hillside down on the road because of frequent earth quakes. So enjoy the magnificent sceneries but be careful when you drive there!