Try this:
1. Type
LPKSETUP in the Start Menu’s search box and press Enter on the keyboard.
2. Click Next in the Install or Uninstall display languages window.
3. Select the option to Uninstall display languages.
4. Check mark the language pack(s) you want to uninstall and then click Next.
5. When the language pack(s) have been uninstalled click Close.
This tutorial may also help.
Display Language Packs - Install and Uninstall