After you get the confirmation that your system can run Windows 7, there are some preparations you need to make to avoid getting burned if something goes wrong during the upgrade.

First up, make sure to make a disk image of your XP machine as it exists now so that, if you later decide Windows 7 isn't worth the disc it's written to and you want to revert to the ancient XP, you can do so without a lot of hassle. There are lots of free backup programs for XP, which can create a disk image, a bit-for-bit copy ofthe hard disk. Macrium Reflect Free Edition (in the DVD) is a very good choice and run on XP and let you create an image on a CD/DVD, external drive or flash drive.

Another good thing to do would be to generate a list of applications currently installed on your XP system; since you will need to manually install all the programs you want in Windows 7. And also it would be a good idea to retrieve the license keys of the programs installed. For this particular task Belarc Advisor (in the DVD) would be the perfect tool. It generates detailed info of your system including the list of installed apps and product keys and displays the result in the default Web browser.