Hello,
At the airport, you can change your euros or dollars. The rate is not the best, but it's possible. If you can translate your passport in russian, then do it, it will be useful in any bank where you will want to open an account. Your Visa/Mastercard won't work, for sure.
You can also go to some banks (Nikobank for example) to change your money in rubble, but they will ask you for a translation of your passport. They give banknotes that they have, it can be 1000, 2000 or 5000 (my experience)