Dealing with regional options varies depending on what version of Windows you run.

This article describes the process of adding input language in Windows Vista.

Step by step instruction:

1) Click 'Start' and click 'Control Panel'.

2) Click 'Clock, Language, and Region'.

3) In the opened window click 'Regional and Language Options'.

 4) Choose the 'Keyboards and Languages' tab and press Settings button.

 6) Under 'Installed Services', click the 'Add' button. The 'Add Input Language' dialog box will appear.

7) Expand the appropriate language and select the text services you want to add.

8) Click 'OK'.