Hi there,
We are adopting in Kaz, and wanted to learn some of the language (although we are hoping for younger than 2 year olds, so the talking part will be different). But we got this cd, and it has lots of "phrases" that you may like to learn in Russian. The site is at:
http://internet.roadrunner.com/~fdd/index.html and we have liked using this (better than the regular Pimsluer type stuff).
I do think there are other "adoption cd's" out there, but this is the one we ran across first. There are phrases like "I am your mom/dad", "I love you", "are you hungry", etc that could be helpful and comforting to a ~5 year old that you will be meeting. This doesn't address your question directly of "what do we say" but may arm you with some things to say once you get past the first scary/exciting meeting!