I just installed Windows 7 on my notebook. I had a licensed version of Windows Vista, which kept on notebook unused for about 4 years. Vista was too slow and even though I didn't launch it for about 2 years after launching I figured out it is broken, it boots about 10 minutes and all the time tries read from notebook Hard Disk. After re-installing with Windows 7, and setting default environment Language setting to Bulgarian I figured, my default input language set it Bulgarian. As I use more latin than Cyrillic this made me crazy as in each Windows I had to press Alt + Shift to change language to EN.
Bulgarian language was set as default even on Windows logon (Welcome Screen).
Here is how I managed to change Windows irritating behavior so my default input language is English:
Start -> Control Panel -> Region and Language -> Keyboards and Languages
From there I changed language to English (UK) then retart and Hooray, default input language is English