Typing in Chinese
Add the Chinese input method:
Start=> Control Panel => Regional and Language Options => Languages=> Details => Add => Chinese (PRC) => leave the default option to Microsoft IME Pinyin
This adds a language toolbar to the bottom (or top) of the screen.
To switch between Simplified and Traditional you need to add the Character Set button on the Language Toolbar. 1) Switch from English to Chinese on the language toolbar 2) Click on the small arrow at the end of the language toolbar and select "Character Set". There is a detailed guide here:
In Word, to add translation from Simplified to Traditional (and vice versa), you need the proofing tools. The option is under Tools => Languages after the proofing tools are installed.