for MyCatIsABigger....
re linux, better or not, than Windows...
primary difference is that different versions of linux have been developed and are offered for free (though someone putting linux on a CD is allowed to charge 'reasonable' fee for the CD and time, as it makes life a bit easier for someone else than downloading it and then burning a CD themself).
Major items of software have been developed (again, mostly for free) by programmers with an altruistic side, where a 'thank you' (or a $10 donation) is the type of recognition they welcome.
As a result of linux being free, the majority of items of software that go on top are also free, or low cost, compared with some applications for Windows, and Windows itself.
We're used to things like Firefox, or Opera, being free, but browsers have not always been free (in the early 90s you needed a licence for Netscape Navigator, and I bought a copy of v3 in San Francisco in 1995, and Opera only became free {rather than advert supported} when it got to their 10th anniversary, and because Opera is used in many mobile phones, so they have money coming in from phone makers now).
In general Windows has become a bit slower (made up for by much faster computer CPU, and needing lots of RAM) each time a new version is out. PC makers don't mind, as many people need to buy new PCs to run the latest Windows. The 'bloatware' nature of Windows (hundreds of programmers working on different aspects) is not copied for Linux. While there have been lots of people involved with developing Linux versions, the end result normally runs fast, needs less RAM, but (before Open Office came out) had fewer 'office' applications, so wasn't taken seriously by big business.
One area where it still has a big market share, however, is on the internet. Linux can be used on much smaller machines, such as routers, dedicated to specific tasks (without the overheads of a big 'graphical' interface like the Windows desktop), and a good proportion (probably in excess of 75% of web servers are running Linux - it runs for weeks without needing a reboot, while Windows servers often need a reboot every week or they get sluggish through memory mismanagement.
A few forward-thinking organisations have moved to Linux, as they don't have multi-thousand pound Windows licence fees to pay (assuming they have hundreds of users), Open Office is free vs MS Office 200x, and they don't need to upgrade PCs to allow the latest version of the OS to run.
Most versions of Linux these days have a graphical interface, desktop and so on, like the Mac or Windows, so getting to be as 'user friendly' as the others, but not yet caught on as much, because firms like Dell don't push them very hard - and some dumb (sorry!) customers will choose a PC on price, find it runs Linux, and bring it back, as they need want Windows (they groan because it looks different, didn't really give Linux a try, and rather than persevere, take it back).
Wal*Mart (owner of Asda) sold Linux PCs for about $200 near the end of 2007, but they probably have salespeople who only know about Windows at home, but checking today they only sell linux books
However, other firms like Sub300.com and Sub500.com in Canada have been selling PCs at under US$300 for years - I came across them when they were doing a deal where they'd install Linspire v4 on any working PC sent to them and ship it back, for the cost of the return shipping, or send Linspire CD for some low fee {I asked, they said 'OK' and I got a CD, for same cost as if in USA, as they put it 'had not said USA only', and I was expecting some heavy postal cost, or a stark 'No' but they didn't seem to mind!)
They're clearing out machines and so forth for prices from $99 to $160 (that's about 60 to 100 quid, plus 20 quid delivery to USA)...