Usually, when we say our wishes to someone who has birthday, we say "Χρόνια Πολλά". The first word means "Years" and the second "Many". So, for now, I 'll try to write something about pronunciation, which is something like "hronia pola", "h" like "hammer", "o" like "or", "a" like the first "a" in "language", "ι" sounds like "i" in "is" (or maybe like i in yunani:)), but some dictionaries prefer the letter j because in this word "ι" doesn't sound very clear. Anyway, it would be easier if I had send an mp3:)

here's an interesting online software I've found for the pronunciation of short phrases, like the one you're asking about: http://www.oddcast.com/home/demos/tts/tts_example.php?sitepal select Greek as language and type your text in Greek. Then click 'Say it'!! :))) I checked it for 'Χρόνια Πολλά' with the speaker 'Afroditi' and it was perfect. Check it out.