When your computer keyboard stops being predictable, and pressing the "q" button gives you a Russian "ya" letter, or your "@" sign is suddenly in a different place, it can be a nightmare to type anything. Changing your keyboard back to English, however, is quite easy on any operating system.
Windows 7 or Windows Vista
Hover your mouse over the two capital initials that are found on your taskbar (on a standard layout: at the bottom of the screen). For example, if the taskbar shows "FR," the keyboard's language is set to French.
If the letters on the taskbar are not visible, look for the language bar on the top of the screen, which will show two capital initials, a language, country, help button and drop down button e.g. FR French (France).
Left-click on the initials and select the "EN" (desired country) from the drop-down list. Keyboards between English speaking countries can be different and you should select the appropriate country. If there is no EN option available, left-click on Options, then click on Settings and then on Add. Choose your required EN input language and EN keyboard layout.
To change via the keyboard hot keys, hold the keys left ALT and SHIFT to quickly shift through your various languages, or go to Options in the language bar, select Key Settings, chose your desired version of EN and left-click Change Key Sequence. This will prompt you to choose your own shortcut to change the keyboard to that language.
Alternatively, Microsoft says you should "click Start, then type intl.cpl into the search box, go to the Keyboards and Languages tab, click keyboards, then add your chosen version of EN by selecting it and clicking OK. Then click on the default input language, select your chosen EN and click OK twice. In the Regional and Language Options dialog box, click OK."
If none of the above steps work, click on Settings and choose Restore Default. This should switch the keyboard to EN (U.S. American) English and allow you to manually add any other EN languages using Steps 1-3.