Don't think that will work hey. Try googling it. Or contact activision support.
Assuming you have steams mw2, change the language on the steam mw2 by right clicking the game, properties and click language change
it to Russian and wait for the files to do what they do. Go into Fd1 and it should be changed!
If you have Steam MW2, you can change the language in the settings (tiimevexx already said that).
Else you'd need to download the russian "zone" folder but its very big and I don't think that you'll find it anywhere.