I've been using MS Windows since version 3.1 and ever since Vista is the only OS by Microsoft which I haven't even tried; and I'm glad I didn't. No comments required on this. However I must say the next effort by Microsoft, i.e. Windows 7 is commendable. I tried to switch over to Mac but the non-standard shortcut keys of Mac for a keyboard ninja like me, and a few minutes of usage with Release Candidate new OS successfully proselytized me to Windows 7.
However Windows 7 doesn't have built in support for upgrading from XP. One could follow the painful procedures of upgrading XP to Vista first and then to 7 and struggle with driver issues. Here is a much convenient way.
For me, the most important thing was to retain my profile settings and then my programs as well.
Windows 7 comes with a utility called Migration Wizard. It lets you backup your settings and restore on a fresh install.
To use it, just boot your Windows XP and insert your Windows 7 installation disc. From the folder \support\migwiz\ run migwiz.exe. It'll let you choose the stuff you want to backup. Keep the file at a safe place (e.g. a USB disc). Now install Windows 7 and run the same tool. This time choose the restoration option and point it to the file in which you saved settings. It'll take some time but it is worth it.
Here is a detailed tutorial: http://www.howtogeek.com/howto/3179/migrate-xp-to-windows-7-with-easy-transfe...