How to switch the KeyboardLayout for all Application at once

"From the research I did, I found no way to do this through windows; I think it is hard-coded.

However I found an application that provides this behaviour: Keyla. It is even open source, so you can be sure there is no funny business going on."

"If you want to change the system language; Microsoft does not deliver this settings for every version of windows. Only the Ultimate Version of Windows 7 is capable of this.

Take a look at the following links:

http://answers.microsoft.com/en-us/windows/forum/windows_7-windows_programs/language-in-windows-7-ultimate/eb2fba1f-bbb9-424a-a3da-770ea0df4da6
http://support.microsoft.com/kb/972813

If you only want the keyboard layout changed this question is duplicate of the question answered here:

How to switch the KeyboardLayout for all Application at once"

"Kubuntu
You may want to have access to more than one keyboard layout. This is useful if you write in more than one language.
To add new keyboard layouts:

Choose: K-Menu->System Settings->Regional & Accessibility->Keyboard Layout

In the Layout tab, check the Enable Keyboard Layouts box.

Choose the country in which the keyboard layout you want is used, and click Add. The country should appear in the Active Layouts list.

Click the country in the Active Layouts list, and choose the appropriate Layout variant for the country selected. This is important for countries where more than one language are commonly spoken.

Click on Apply to save your settings.

A flag icon should now appear in the system tray showing the current keyboard layout being used. Click the flag icon to switch to the other keyboard layout.
Source: http://linux.about.com/od/kubuntu_doc/a/kubudg38t11.htm

Windows

Click Start and then Control Panel

In Control Panel, if you are in Classic View, click on Control Panel Home (top left corner)

Open Clock, Language, and Region

Click on Regional and Language Options.

Click the Keyboards and Languages tab and then click Change keyboards.

Under Installed services, click Add.

In the Add Input Language dialog box, select the keyboard layout you would like to add from the list available and click OK.

The keyboard layout you added will be included in the list. To set the new layout as your default, select it from the list. Click OK to save your changes

You can switch between different input languages (= keyboard languages) by clicking on the Language Bar button or by pressing the Alt + Shift keys"