Best Microsoft OS - Ever

I have been using Microsoft Operating systems since "DOS 5.0" a few years ago. Definitely, Windows XP with Service Pack 2 is the most refined desktop operating system Microsoft has ever come up with (including the newly released and quite disappointing Vista OS).
Service Pack Two includes countless security enhancements and bug fixes making this OS highly stable and solid. A software firewall is now built in and many safeguards now exist to foil most hacking attempts. Of course it's wise to have a hardware firewall/router and good virus protection software with any operating system from Microsoft or other vendors.
While not quite as resource efficient as previous versions, XP is a good balance of resource utilization and features. Built in ZIP archive management, image thumbnails, and remote desktop access are just a few examples of very useful features XP has to offer.
Having been on the market for several years now, almost any type of printer, webcam, scanner, or other accessory is supported by XP. Not only does XP support more hardware then any other OS, "plug and play" makes setting up most hardware very easy. Any current computer, even quad-core power machines with 3GB of ram will run happily on XP (people with 64bit processors may wish to take a look at the 64Bit version of XP) and most anything made in the last 10 years will be happy with XP running on it as long as it has a minimum of 256MB RAM. I would recommend 1GB of ram for running XP at peak efficiency though.
Gamers should look no further. No matter what anyone might say, there are more games that work on XP then any other operating system of any kind anywhere. If you are looking to play games on your computer, there is really no competition out there to speak of...just use XP.
For office productivity, XP supports everything from OpenOffice.org to Lotus to the latest Microsoft Office 2007. And the interface is the most recognized and proven productivity-efficient out there at this time.