If you're a committed, heavily-invested user of a specific language, and well into your professional career: use that language.
Otherwise:
If you like Python, Django.
If you like Ruby, Rails.
Otherwise: Flip a coin.
Heads? Rails.
Tails? Django.
A lot of very smart people will tell you that PHP is as good an option as Rails or Django. The problem with PHP is that while the upside for PHP is, as they're observing, just as good as the Rails/Django upside, the downside is way worse.
Counterintuitively: I think you should really know what you're doing as a developer before you decide on PHP. PHP isn't by itself going to teach you to be a better developer. Python will.
Avoid Javascript frameworks until you really understand what you're doing. Also, know ahead of time that "really understanding what you're doing" might result in you continuing to avoid complicated Javascript. A trap I can tell you about from recent experience. :)
Probably don't build front-end web applications in Go.