Airport Sheremetyevo 2 in Moscow is like most small Airports in North America but a little less modern, and badly in need of some air-conditioning and lighting. Expect long waits through Passport Control, at least one hour. Don't expect the Girls in Passport control to be to friendly. Consider yourself flattered if they smile. Then pickup your bags and keep a close eye on them and go to one of the small tables and fill out your customs declaration if you didn't get one on the plane, hopefully you will find one in English (don't lose this declaration, you can't leave Russia without it!). Next proceed to the Money Exchange booth (Valyuta) and only cash a hundred dollars (Russian inflation is very high). It is best to exchange American Currency or German, as Canadian is not accepted everywhere in Russia. Next go through Customs, there is two Customs check-ins. One if you have nothing to declare and one if you do. Again don't expect many smiles if any. Don't be overly pleasant with them, they will just get suspicious. Then if you don't have transportation waiting for you, good luck! You will need the services of a Taxi (no Metro service to airports). If you are transferring to another Airport, expect to pay at least $100 American to get there, try to share a taxi with another person from your plane if anyone else is also going to the same Airport as you. There are buses going to the other Airports, but unless you speak Russian and understand the bus system, don't even bother trying. You will just end up missing your connecting flight or worse.
Please note that Russian X-ray machine at the airport is not film or laptop computer safe, step to the side and show your film and laptop for inspection. You must insist or the Russian Customs Officer will put it through the X-ray machine.
The other four Airports in Moscow, Sheremetyevo , Domodyedovo, Vnukovo and Bykovo are extremely difficult to understand, as they are not tourist friendly. You must have your baggage weighed first, as you are only allowed 20 kilos maximum per person, then you must pay about $1 US per kilo thereafter. You must then know where to check your baggage in, everything is in Russian so hopefully someone will help you. Be sure to get your luggage claim ticket, or may never see your luggage again. Anything of expense keep with you, don't check it in. Please note that there is no real line up to check in, it is every man, women and child for themselves, be forceful or you will never get your bags checked in. Then you must proceed to where you show your boarding pass (ticket) and then wait in the waiting area till boarding. If you don't understand Russian, ask, ask, and ask again, till you find someone that will help you find where it is you must go.
As for flying in a Russian airplane for internal fights within Russia, you could be playing with fate. They are not well maintained and crash regularly. As for Aeroflot, no problem, they use Boeing planes and must meet certain requirements to land in International Airports. WARNING, DO NOT TAKE PHOTOS AT THE AIRPORT! THEY SEEM TO HAVE A PROBLEM WITH THIS. YOU CAN BE DETAINED, IT HAPPENED TO MY WIFE.