Advantages of Linux
I do like that part!
Philosophy
Linux is free and you can get it for free. You do not need to pay dozens of Dollars/Euro to use it legally. If you purchase a commercial distribution such as Red Hat or SuSE, you can use it for any desired number of installations. This is a major point: Imagine the costs companies could save if they did not need to pay the Microsoft licenses.
There are millions of Linux users worldwide and most of them help each other by developing, debugging, translating and supporting Linux. All of them want to improve Linux and its programs together. In mailinglists you can contact the developers of your favourite program and ask them diretly.
Core
You have full control of the system: You can terminate programs that have crashed but Linux itself and the other programs are not affected. You can restart only the services that you has re-configured (e.g the ip-address), without restarting the whole system. That is very important for big servers on the internet that depend on each second of online-time.
You can control the allocation of the PC's resources (CPU and RAM) by setting an appropriate priority or "nice level". In so doing, the user has the ability to control how the Operating System time-slices the available resources among several processes. For a background task that you want to run only when nothing else is happening you set the priority level to a larger number (lower priority). The highest priority you can set is actually a negative number (-20). Setting something to run at that highest priority will cause the scheduler to give that task much more of the PCs resources than other processors are getting (over a particular unit of time).
Once, a device (e.g. a scanner) is supported, it will be supported in future. You do not need to hope that the manufacture write a new driver for a new version of the operating system.
User Interface
In Windows there is only one standard user interface, you really get sick of soon. The new Luna style in Windows XP is not a solution since most people deactivate it due to its ugliness. Using Linux you get a great choice of styles. You may check art.gnome.org [en] and kdelook.org [en] or the recent shot of my desktop.
Another point is the usability: If you work with several programs on the desktop at the same time, you may want to move the windows several times. Using Windows you have to drag the window in the status-bar, using Linux you can just press a single key - mostly the "ALT-key" (depending on your window manager) then click-and-drag somewhere on the window to move it. You can also define several desktop groups making your desktop(s) more clear, e.g. one group could be programs having a similar task.
Linux vs Windows
Recently, more and more enterprises and public institutions move not only the servers but also the desktops to Linux: e.g. Merrill Lynch [de] and Unilever [de]. Microsoft has been very eager to make the town Munich not to move to Linux, so that Steve Ballmer has even interrupted his holidays. Despite price deductions that has made the MS offer cheaper than the Linux offer, Munich has choosen Linux [de] because of strategic causes not to depend on Microsoft.
Imnage that firms negotiate with Microsoft in a stronger position since the firm can threaten with the move to Linux! But Microsoft tries to proove that Windows is cheaper than Linux with studies that they paid themselves [de]. On the other hand there are studies that say that desktop productivity of Windows of Linux is almost equal [en|de].
These studies mirror the inteterestings of the orderer, since the conditions can be be adjusted to those. The costs can also be calculated in several ways and the considered period is also adjustable. Thus, these studies should be considered carefully no matter what is the conclusion.
But I guess that Windows is not that important for Microsoft but MS Office since MS Office is the cash cow. If a firm moves to OpenOffice.org it can save a lot of licence cost but keeping Windows. So, they can better prepare to the possible move to Linux with a better position in the negotiation since OpenOffice.org does also run on Linux well.
