Re-learning Russian

Ms. Sandwalk and I are going to be in St. Petersburg (Russia) in a few weeks. We plan on spending four hours in the building on the right (and adjacent buildings) although I'm told that's not nearly enough time.

I'm trying to remember my Russian. I last studied it in high school 50 years ago. We've been watching videos of the main tourist spots in St. Petersburg and I can usually figure out what the signs are saying. For example, it was pretty easy to recognize the sign below. In fact, most of you could probably figure it out even if you haven't taken Russian.

Here's the problem. The language in most Western European cities is quite casual compared to the way it was in the past. A typical greeting might be similar to "hi" instead of "How are you?" The comparable words in Russian are Привет and Здравствуйте. Which one is more appropriate in Russia today? And which pronunciation of Здравствуйте should I use?

Similarly, I was taught to say Как вы поживаете (How are you?) but that's a very formal phrase. I get the impression that it's now thought to be archaic and you can easily skip the pronoun by saying Как поживаете. Can you get away with addressing a stranger using the informal first person version of "you," e.g. Как поживаешь?

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