I see. I have a bias towards Ruby and Rails because that's what I do. I've never used Python or Django, but I've heard that they're comparable.
That being said, I would recommend you learn Ruby 1.9.2 and Rails 3.1. The community is great, the framework is amazing, and there are a lot of resources freely available, like Railscasts, to help you along your way.
I would stay away from PHP and Java.