Today, I will introduce you to the joys of Open Source software with a special mention going to the Linux Distribution.
Let's take it one step at a time. Windows comes in different varieties, for example, XP, Vista, 7 and so on. So does Linux, however there are some fundamental differences between the two.
At the time of writing there are literally hundreds of Linux Distributions available from hundreds of different companies all offering their own "flavor" of Linux. Since there is no one company in charge of Linux development distributions can fork off and take their own direction, for example Slackware is aimed at the Linux pro where Smoothwall is a dedicated firewall. Chances are there is a distribution which fits your own personal criteria.
OK, so which one is best? Well this depends on your own point of view. Linux pros might like Slackware or Gentoo, intermediates with some knowledge of Linux might like Fedora while total newbees might like Ubuntu or Mint. Your best bet is to take a look at Distrowatch to see a list of all the distributions and pick the one that suits you.
This is where Windows users will usually perk up and say Linux is rubbish, it has no support, no packages, you have to use the command line all the time and it is not compatible with anything. Lets use Linux Mint 12 as an example. Linux Mint 12 comes with the option of 30,000 packages for you to download if you wish. Does sir want a package to play their CD's on then how about Rhythmbox or a package for pictures then use GIMP. You see there is a package for just about anything you could wish for.
What about support? You can use the online community forums for your distribution for hints and solutions on how to fix any problems that you might have (in the same way you do for windows). The thing is that you will probably have less things go wrong with a linux system than you will with windows.
As for the command line you can use it if you wish but it is not necessary. It is true that to fully understand Linux the command line is essential but if you only want to browse the web, download packages and just do all the usual stuff then you don't need to go near it.
So lets round up. Linux HAS support, Linux HAS thousands of packages, you DON'T have to use the command line if you don't want to and IS compatible with all the standards (just save stuff as a doc file for instance). It is also more stable, free (no license fee) and you DON'T have to worry about viruses. Go on give it a go!