If you want to change the language that Windows uses in dialog boxes, menus and other items in the user interface, follow these steps:
1. Open Regional and Language Options by clicking the Start button, clicking Control Panel, clicking Clock, Language, and Region, and then clicking Regional and Language Options.
2. Click the Keyboards and Languages tab.
3. Under Display language, choose a language from the list, and then click OK.
If you don’t see the list of display languages, you need to install additional language files first.
Note: You can install additional display languages in Windows 7 Ultimate and Windows 7 Enterprise only.
To download and install additional language follow these steps:
1. Start Microsoft Update. To do this, click Start, type Microsoft Update in the Start Searchbox, and then click Microsoft Update in the Programs list.
2. Click the optional update links for the language packs.
3. Under the Windows 7 Language Packs category, select the desired language pack.