I don't think that a strict "convert my program from one language to another" is a good question. It's basically asking people to write the entire program for you, so it's not too different than that class of highly disliked questions. Stack Overflow is no more a place to free-commission code translation as it is a place to get people to do your programming for you.
However, code conversion itself is a legit topic. I know I've seen general "How do I convert this language to this language safely?" questions, and a similar class are the "How would I replicate the effects of X that I do in my language, using another language?" questions. Any vague "convert my program from one language to another" question can basically be broken down into these component parts, and either asked as their own individual questions or the answers to the components sought out. That would be the proper approach to trying to tackle a program conversion... research the methodology for general case translation, then highlight the topics that aren't covered.