There should not be any problem with activation - naturally one is free to travel and it just might so happen that one experiences a problem and needs to reinstall in a foreign country. Thus it's only logical that you can activate your legally purchased Windows regardless of your current geographical position.
Now, the localized versions - such as your Middle East one - are usually not in English, but in the local language. That's the number one reason to have such a localized version. However, Windows 7 is great - you can download any language pack from Windows Update and change the language of your OS to whatever you want it to be. I believe it's still useful to know the original language of the localized version, in case it might show up in some circumstances, but I believe this should not be a problem for you.