Technically, Linux is just the kernel, which is really a pretty small component of a usable system. It takes a lot of additional software just to get a system that can boot, let alone one with a nice GUI and useful tools.
A distribution is a collection of various free open-source software set up to be a usable system. For example SuSE and Ubuntu are both based on the Linux kernel, but use entirely different graphical environments, different package managers, and have very different default setups and installed software. They're both Linux distributions, and both are based on the same underlying software (usually you can count on the Linux kernel, GNU userland and X.org X server), but are quite different operating systems.
You can't really draw parallels to commercial operating systems since distributions all bundle similar software, they just do it in different ways, driven by different goals and cater to different uses. Furthermore they all build off each other's work, with the good bits developed by one distribution being used where they fit in the philosophy of other distributions.
You need to just try them out (or at least read their 'mission statement') and see what fits for your usage. For a desktop I'd suggest you try Mint (or Ubuntu, they're very similar) and Fedora for a start, they're both large and have a good community behind them. For servers look at Debian (my personal pick..) or CentOS, or perhaps SLES.
A distribution is a collection of various free open-source software set up to be a usable system. For example SuSE and Ubuntu are both based on the Linux kernel, but use entirely different graphical environments, different package managers, and have very different default setups and installed software. They're both Linux distributions, and both are based on the same underlying software (usually you can count on the Linux kernel, GNU userland and X.org X server), but are quite different operating systems.
You can't really draw parallels to commercial operating systems since distributions all bundle similar software, they just do it in different ways, driven by different goals and cater to different uses. Furthermore they all build off each other's work, with the good bits developed by one distribution being used where they fit in the philosophy of other distributions.
You need to just try them out (or at least read their 'mission statement') and see what fits for your usage. For a desktop I'd suggest you try Mint (or Ubuntu, they're very similar) and Fedora for a start, they're both large and have a good community behind them. For servers look at Debian (my personal pick..) or CentOS, or perhaps SLES.