Now you do not need to worry about upgrade the system without losing any data or function. So how you will do this we are going to explain it. There is great facility for this purpose which is free Upgrade Advisor utility which is for hardware as well as software and can work also in windows 7.Now the first thing is to make sure that your hardware is compatible for upgrade or not. If not then you need to purchase upgrade. Windows 7 Upgrade Advisor is use to check the hardware. And if you are running windows vista then your hardware is capable of windows 7.Here the one of most important thing is that do you wish to upgrade your windows installation or you want to install fresh windows. The upgrade is much easier like your applications, settings, and data travel with you.When you will have clean and fresh (Microsoft's word) custom install then you can set up your users and networks, reinstall your drivers and programs, and move your data back into place.Custom install is better choice rather than upgrade. This is garbage for the windows that you use and flush it. So you have start new version of operating system.If you are the user of XP then there is only the choice of custom install. These instructions are for both kinds of installs.
How to Upgrade Windows 7