If your screen is not displaying the Cyrillic text properly, you can change the encoding of your web browser.
To do this, go to "View" on your browser, then "Encoding", then "Cyrillic (Windows") or other appropriate encoding.
Cyrillic KOI8-R is generally considered to be the standard for sending and receiving email in Russian.
The following links may be helpful if you are having difficulty configuring your keyboard to type in Cyrillic:
"Russifying your computer" (American Association of Teachers of Slavic and East European Languages)
BRAMA Computing and Software
If you are on a public computer, and cannot change the settings, you can still type in Russian by using virtual keyboards such as: