Should You Upgrade to Windows Vista?

No.

OK I will elaborate further. Windows Vista just isn't that revolutionary leap over XP. If you have Windows 2000 SP4 or XP there just isn't a compelling reason to make the jump or the expense of getting the software. That doesn't even include the cost of possibly upgrading existing computer. Pretty much the rule of thump with Microsoft is to double whatever their minimum system requirements are. In this case that means your computer should be at least a 2.0GHz computer with 2 gigs of RAM. It also means that to get the full experience, you want a separate graphics card not the imbedded one that comes with most computers.

So expense aside what about the bells and whistles? Well, there are some improvements in stability and security, but not enough to be worth the expense. Want to know more about the features Engadget did excellent job summarizing Vista's improvements (or lack of) compared to XP.

Vista is supposed to be a boon for a gamer, but that boon isn't going to be realized just yet. Part of the problem is there doesn't exist any games on the market that use DirectX 11. No game for it no advantage to having it. So you have it but it and that’s about it. Also Vista is just a general resource hog so it’s more then likely to hit the game performance. Also it turns out from test by PC Perspective, the ATI and NVIDIA graphic card drivers are not yet up to snuff so I would give them more development time if a gamer.

Maybe you love your multimedia files and feel that Vista will allow you take full advantage of them? Well no, the experience difference is minimal, usual HD standards are handled by the graphics card not the OS. Also Microsoft has added security to help the war against copyright infringement by bending over backwards to appease the RIAA and MPAA such as technical limitations in the OS to perform certain tasks. If you install Vista, you are agreeing to grant Microsoft the right to check the legitimacy of software on the computer and delete it without permission. These and several other "security" measures are aimed more at protecting big business interests rather then your own.

Long story short, if your computer is more then 6 months old, Vista really isn't for you as will incur upgrade expenses if you want to enjoy the full experience. Nor does the overall lack of leap in improvements make the expense worth while. You are basically paying a heap of money for presentation and not much else. Vista might be worth the cost in another year or so, but for now, just wait and get it whenever you replace your current computer.

Links of note:
Upgrade Guide To Vista Software
Upgrade Guide to Vista and Hardware
Review Roundup