Welcome Tina, first the Century is beautiful, we loved our balcony cabin. I worked with Denrus from home via the web before we went. With thier help we planned a 2 day private tour to all the places we wanted to see. The ship even had a meeting place for all passengers using DenRus to meet in one of the Bars and they took us off the ship to meet our guides, they were waiting with a sign with our name on it. We had an english speaking guide, driver and private car.
If you do this you will see so much more and go to places the ship does not. We had lunch both days where we saw no tourist, loved the food, we had to try borscht and authintic chicken kiev, our guide told to try a shot of vodka too!
We went to Church of the spilled blood, Catherine's Palace,Hermatige,Peterhof Palace,took a hydrofoil ride back to the city center, took a tour of the Metro, Yusopov Palace, St Isaacs Cathedral the Fortress. Our guide took us to a few non tourist shops. She was wonderful and new so much history it was fantastic. We would drive up to a place the Peterhof Palace and see lines and lines of people and she would get us in the back door in front of the lines. We felt this way how often are we going to go to St. Petersburg, so let's do it right. Worth every dime if you can do it. We ran from 8am until 6PM both days. Wished I was going again. You will have such a wonderful time. Let me know about your trip and the beautiful Century!