This is an excellent free book: http://www.greenteapress.com/thinkpython/thinkCSpy/ (you can download the PDF version and start reading, or order a print copy)
It explains how to think like a computer scientist, and then applies those concepts to Python.
Python is particularly good, as you can use it to both write desktop applications and web applications.
You can worry about that later though; just get started with How to Think Like a Computer Scientist to start learning the basics. By the end of the book, you’ll be writing pretty advanced code and will probably be interested in further learning with something like Dive into Python.
Python is a pretty simple language when it comes down to it, but is also nice and rigid. There’s a million ways to do the same thing in languages like PHP, and your code can potentially end up being really ugly because there’s no enforced conventions for ordering and indenting things.
In terms of how easy something is to learn; Python is far superior because you’re not constantly seeing the same things done in different ways.
I highly recommend Python and hope you enjoy it.
Fluther is actually written in Python and Django, an excellent web framework (a framework is like a set of building blocks) for Python that allows you to handle requests from web browsers easily.
Once you’re pretty good in Python, check out PEP 8, which tells you even more about the standards and conventions you should be thinking about to write good Python code.