Greek as a 2nd language ?

Has anyone accomplished learning Greek? DuoLingo is about to launch their Greek lessons but I have been so frustrated with it. I think mainly because even if I have the alphabet memorized, i still can't translate words for some reason. A lot of online resources haven't really helped, either. Should I learn another language first before moving onto Greek? I'd love to learn it because of the challenge, but I need more in depth lessons and I can't find them anywhere.