Has any OS been so maligned and so praised during a painfully long development cycle as Windows Vista? The march to Vista's launch has sometimes seemed longer than the Hundred Years War.

Now that Microsoft's new system is at hand, the debate can begin. Is it a look into the future of OSes or the last, dying gasp of an old way of computing? Should you upgrade your system to meet its considerable hardware needs? Is it anything other than Mac OS X Lite?

Some may complain that Vista isn't as revolutionary as it should be after five years. But you don't judge an OS by the amount of time developers have put into it. You judge it by how useful and how pleasurable it is to work with – and in these respects, Windows Vista is a clear winner. It's beautiful, has greatly improved security features, offers superb networking capabilities and, maybe most of all, it's fun to use.

There are so many new features in Vista that it's hard to take them all in at once. To help you, we've broken down the key aspects into four key categories, all of which bring significant improvements.

Aero interface

Click here for PC Advisor's review of Vista's new Aero interface, which revolutionises your view into Windows.

Security Center

Click here for PC Advisor's review of Vista's new Security Center, which attempts to put protection at the heart of the operating system for the first time.

Windows Search

Click here for PC Advisor's review of Vista's search tool, Microsoft's best-ever attempt at helping you find files using a Windows tool.

Bundled applications

Click here for PC Advisor's review of Vista's built-in applications, an area in which the OS far surpasses Windows XP.

That's not to say it's perfect – far from it. Some may view the new interface as little more than fluff or be turned off by the intrusive User Account Control feature. Expect a long-running discourse between Vista lovers and haters. Which camp will you fall into?

We'll help you decide by looking at the new features of Windows Vista in depth. We show you: how the Aero interface revolutionises your view of Windows; how the Security Center attempts to put protection at the heart of the OS for the first time; and how finding files and even connecting to networks has never been easier.

As well as looking at the Aero interface, Security Center and Vista's new networking and search functionality, we've reviewed the best new Microsoft applications that are bundled with Vista for free.

The highly anticipated Windows Sidebar puts customisable information in front of you every time you look at your screen, while the Windows Calendar and Windows Mail should make day-to-day tasks slightly easier than in XP. But not all of Vista's bundled apps are worthy inclusions – click here to find out more.

Once you've swotted up on Windows Vista, it's time to make your decision. Should you upgrade to Windows Vista? And if so, how? If you’ve got a Windows XP system, it's likely that your PC will be able to handle Windows Vista to some degree. Whether that’s in its most basic form, or with the full benefits of the new Aero 3D interface, depends on your current specification. In the March 07 issue of PC Advisor we look at the upgrade process in depth. We outline the various requirements, and show you how to prepare your PC if you decide to make the leap.

But forking out for a new operating system, or even a new PC with it installed, might not be for everyone. In the March issus we also show you how to revitalise Windows XP to make sure it continues to fulfil your needs. With a few tweaks, there's no reason why your current system shouldn't continue to serve you for another couple of years. Either way, it's decision time.

The bottom line

All in all, Windows Vista is a great leap forward for the operating system, with a much-improved, far more intuitive interface that's a pleasure to use. It offers faster, better search, beefed-up security that's a big improvement over Windows XP with SP2 and far, far better networking. There are some clunkers in there, though, such as the annoying UAC feature (read about that here). It's fair to say that Vista is better than XP, and there are many advances that show that Microsoft has thought long and hard about the way people use Windows.

The user experience and the revitalised appearance are significant advances, and most people will immediately take to the new OS. But is it good enough to justify an immediate upgrade? You can probably afford to wait until your current PC is on its last legs before buying a new PC. But if you want to keep up with the bleeding edge of technology, and make the most of the innovative applications that will make the most out of Vista's advances, the temptation to upgrade sooner rather than later will be hard to resist.

Read our comprehensive guide to Windows Vista in the March 07 issue of PC Advisor, available now in all good newsagents. Click here to visit our dedicated Windows Vista forum.