I\'m globalizing a Windows form application.
Is there a way to access common text in the current language for Windows?
For example, for the labels of OK, C
Yes, theoretically you could extract localized strings from Windows's internal system files. But don't do it. The advantages are far outweighed by the possible disadvantages. Your application shouldn't be reliant on undocumented implementation details. There's no reason to try and get this from Windows.
It's also worth pointing out that you can rename buttons (and every other control). That means it's too easy to break something if you're relying on some kind of string matching algorithm. There's no way to mark a button as being a certain "type" so that it will be automatically associated with a particular caption, and even if you could, this wouldn't cover every button present in a non-trivial UI. Also, as Joey's answer points out, there's nothing worse for the user than a partially localized UI. Consistency is the key, and you can't localize labels, group boxes, menus, tooltips, etc. this way.
Note, however, that Windows will automatically localize the captions for buttons on a message box (MessageBox). You don't have to lift a finger.
What's wrong with setting the form's Localizable property to True (you must do this at design time) and providing localized text for all of the controls in your application? Windows Forms actually has pretty comprehensive support for localization; the designer will automatically serialize all localizable elements to the form's RESX file. See MSDN: Walkthrough: Localizing Windows Forms. Make sure that you leave a sufficient amount of space to allow for the varying lengths of expressions in different languages.