Well as Windows 7 (Vienna) is primed for release soon
As welll as research into any upgrade (a big percentage of any mcp operating exam is about the installation both the prep and partaking in it) the old if it ain't broke don't fix adage comes to mind.
Do you really did to upgrade for what you are doing at present? Have you tested the upgrade on a vm or a spare pc which you are not reliant on?
The pc is vital to many peoples everyday lives so like Mr Admin says best to research, test and trial first before jumping in. Many Firms including IT based firms have not upgraded the OS as there is simply no need let others be the crash test dummies.
W2K only dissapeared off many work PC's i saw around 2005/2006 and still see it quite often. With standalone (non networked) machines many IT firms will leave it chugging away untill the PC dies it seems.h
At the moment they think vista is just 13 percent of those online.
The upgrade problem was the same with all previous versions of windows notably when 95 hit the shelves.