Unicode support for windows is there for ages. But I always felt like something is missing – the good old school phonetic keyboards. You can learn to touch-type of course, but I found my speed of thinking to be the bottleneck and not my typing speed. So if you are already used to QWERTY you can be a bit lazy and take these guys. Standard package built with MS keyboard layout editor.
Russian doesn’t have so many extra letters, only 33, so you’ll have to remember only a couple of them.
Armenian has slightly more, and occupies pretty much all of numbers, and not all sounds are that obvious.
No Chinese. Sorry!