Large Enterprises Dilemma
Adding to all of this is the sheer difficulty of changing operating systems in a large enterprise. Do you simply decree that all future purchases be Windows 7, and then face the expense and complexity of supporting two different platforms? Do you make a wholesale change and end up disposing of computers before the end of their economic lives? Do you decide to keep costs under control by refusing to upgrade? For most companies, especially during the current recession, the choice has been the latter. But eventually that choice has to change. Despite the fact that many companies will wish it weren't so, their computers will eventually cost too much to keep. When they break, parts will be hard to find or expensive, their energy use will make replacing them more economically attractive, and at some point they'll need to buy new machines and XP won't be an option.But regardless of how you do it, the time to change is here. If you really do have machines that are too new to phase out and are also unable to run Windows 7, then install Linux. It'll run better on those machines anyway.
The only real solution will be to start a phased replacement of your Windows XP machines. As they reach the end of their economic life, decide that you won't replace them with another XP machine. Decide you'll get Windows 7, and decide that if you plan ahead you can train the IT staff and ultimately save money through reduced energy consumption.