However if you're serious about becoming a real web developer who likes to get his hands really dirty, then I recommend avoiding PHP and going for Ruby on Rails.
edit - after looking at drupal i took off the line "Drupal might be ok for initial stages but it probably won't scale as well".
Both Rails/PHP are solid choices. If your app fits well within Rails' set of defaults and constraints, you should get to market quicker. PHP has its own set of advantages, such as the ease of procuring cheap hosting and the vast number of trained PHP developers out there that can help build/maintain anything you build.
What is that, hearsay? No, drupal scales fine. Look at the many large sites that use drupal, like the economist, whitehouse.gov and the examiner.
For RoR the standard tutorial is: http://mislav.uniqpath.com/poignant-guide/
After understanding Ruby, http://guides.rubyonrails.org/ is where you should go to figure out Rails.