Linux all the way. Windoze is a dead end. Only stuborness, the same kind of attitude that keeps vbscript alive despite the fact nobody uses it is what is keeping M$ from getting out of the OS game.
In the last few years Linux has taken over the server market. Especially web servers.
Linux was the first OS to use clusters.
Linux has the most advanced and easy to use clustering software.
Linux is easier than Windoze in almost all respects. My last dozen Linux installs have all gone flawlessly except one. The exeption was with SUSE and SUSE is very picky about hardware.
This is generalizations though. The biggest difference between the two OS's is that Windoze is a single tasking single purpose OS. Even the server versions are really desktop machines with some patching to make them servers. NT was an attempt to build a real server OS but it wound up becoming just another desktop.
Linux on the other hand is a group of purposes. There are distro's that are built just for robotics, to imitate windoze, for routers, gateways, firewalls, desktops, music workstations, database servers, SANs, clusters, and a zillion other purposes. Yes they all use the same Linux kernel. However the rest of the distro can be so different that you think you are on a completely different OS. This means you have more than one tool in your belt. Most of all it means freedom. You can build your personal distro if you have the time and inclination. The expertise level to build a distro is not that high. It is time consuming yes. Difficult, not that difficult. Think about it, a custom OS that YOU build for YOURSELF.
Most people don't have that kind of time or really need a custom OS. Linux offers you a variety of pre-built options. Of which one is almost certain to be very close to what you want anyway. It is also easily customizable beyond that to make it exactly what you want.
With Linux you can use GUI or command line or both. You use your computer the way YOU want to, not how M$ dictates to you how you should work.
Linux is free. Most software for Linux is as well. I have 1149 programs installed on this computer at this second. I have about 80 more that I will install over the next 24 hours. There are almost 6,000 software packages availible free from Yum alone. Things like Sound editors, rippers, encoders, image display packages, programing languages, games, editors, etc. That is just the free stuff. You also have a number of comercial packages to do lots of stuff as well. The only ones I've found a need for was to run M$ applications at times when I was in a workplace that had some windoze fanatics.
As for the future. Europe is moving rapidly to Linux. Asia as well. One county in Spain actually passed a law against using M$ software. Germany is slowly moving completely to Linux. China uses Linux for all it's secure applications. Taiwan and France are also heavily Linux involved. Even the UK is moving quite a bit of it's stuff to Linux. 5 years ago less than %1 of the desktops out there ran Linux. Today around %8 are sold with Linux. That is an understatment though. I have a Dell machine for example that runs Linux but Linux was not offered. So officially to statistics that machine is a windoze machine when in reality it's a Linux machine. Dell now offers Linux as an option on many desktops. Sony offers it as the default in Europe though for some reason they do not offer Linux on desktops in the US.
Many city Govs are already running Linux on the desktop. Others are in the migration mode. Oracle is moving all of it's desktops to Linux right now. Ernie Ball strings did so long ago.
Microsoft is one of the biggest supporters and proponents of DRM (Digital rights management.) The Microsoft vision of the world has been for years that to use a program, play a media file or anything else you have to have purchased it and must have the proper keys. Lose those keys you have to rebuy it. Change your computer you have to rebuy it. The first versions of XP actually expired. After a year M$ expected you to rebuy the OS. Until you did you were locked out of your files. This was not M$'s first attempt to do this. Like the previous attempts the uproar from customers caused M$ to remove that "feature" before XP had it's grand release or shortly after. XP initially required you to call in to M$ to get a key to install. Think about it. Do you really want a company like that safeguarding your email, your bank account and everything else you hold private or valuable on your computer? This is the same company that reports your installed software to M$. The champion of DRM.
Using Linux means YOU are in control of your software and what your machine is doing. Anything you don't like, if you have the knowledge and inclination you can change. Most people don't, they run Linux strait out of the distro and only change things by adding software, putting custom desktops, chaning screen resolution and such.
Home networking. Linux home networking works without a problem. Easy to set up. Difficult to mess up. Windoze requires a PDC to be stable as a home network. Otherwise you get drop outs. One day one machine won't see another period. Other machines can see both, but Machine A can't see D and E can't see B and B can't see G.
No more rebooting. You reboot only if you want to power your machine off or to upgrade the kernel. Linux don't crash. You don't have to leave a convo to reboot your machine anymore. No more rebooting just to add a piece of software.
Linux will run forever. I generally upgrade versions only when security patches and support for software for that version start becoming difficult to find. Sometimes a feature of the new kernel is needed or wanted. There are many people today runnign Redhat 7.x versions. You can literally upgrade everything as it comes out. So no more waiting 5 years for the next version of Windoze, then waiting for the service paciks. You want to add support for XYZ then you dowload the latest kernel which supports it and install it. You do have to reboot for kernel updates. That's it. No need to reinstall all your software.
You can actually remove all of a software package in Linux. Sometimes just by deleting it's main dir.
No more virus infections, trojans, and very few worms. Linux by design is far more secure. Unless you run as root all the time most Linux security problems amount to a denial of service.
No more defragging, worrying about or repairing the registry. No need, Linux has no registry or registry corruption. The config files Linux uses can sometimes be a pain but the avg desktop user rarely has to touch them. There are good GUIs on top of the most comonly used log and configuration files now.
More bang for the buck hardware wise. You need less machine for the same performance. Linux's compartimental design means not only is it more secure, if your not using it those drivers usually are not loaded. There is far less disk framentation, the swap disk is on a partition devoted to just that. Something that speeds up performance noticiably.
With yum you now have the easiest method in the world to add and remove software. For most stuff there's no more visiting a web site, downloading a file and then installing it. With windoze you also have to cross your fingers and hope it doesn't crater the registry or replace an essential dll or something else. With yum the software and it's dependancies are already there in the repository. You have a list of the software, what it does. There are CRC checks and other safeguards to make trojaning difficult to do. That's what I'm doing now, just scrolling down and installing packages that I want to try or have needed but just didn't know there was a program to do that yet.
Even Windoze sys admin jobs ask for or require Linux skills today. So you will be running Linux in one way or another if you get into IT.
In short the ONLY thing that Windoze has over Linux is that most game companies (especially since M$ has either bought or threatened them) support primarily Windoze. There are tons of good games out there for Linux. Windoze does have an edge there. All other aspects Linux is equal or far better. Windoze is just now trying to do things like the XP firewall that have been in Linux for years. Unlike XP's joke of a firewall the one that comes with Linux if a first class comercial grade firewall. The same exact software that guards man banks, most of the world's web servers, many of of the fortune 500 companies and more.
Go with Linux. It is where computing is going. Longhorn has been bad enough that with the new CEO I bet M$ goe's with Linux instead of replacing Longhorn with something they wrote. In fact Microsoft is hiring thousands of Linux gurus right now for a huge Linux lab and other Linux projects it has going right now. That to me says it all. This is the same company that has spent hundreds of millions of dollars attempting to kill Linux. Now it's investing heavily in Linux. The writing is on the wall.