If you’re in a foreign country, and you’re in a hurry, and you need cash, the last thing you need is an unclear GUI in your cash machine.
The GUI above, take your knowledge of spanish for granted. You’d better know how your language is spelled in spanish, or you’re doomed.
The following option at least give you a chance in case you’re familiar with flags.
But colonialism, globalization and migration started many years ago. And because of them, flags and languages are not strongly related anymore.
You could make your user’s life easier by means of writing the word for each language in the language itself.
This should be easy at least for language names that can be written by means of Unicode characters. It could be harder for languages with its own alphabet, such as russian, chinese or greek. But if your ATM can work with those languages, you should be at least as good as Wikipedia is.