[citation][nom]Bolbi[/nom]Actually, modern Windows 7 reinstalls don't lose all of your files. Even if you don't back them up (which you really should), the installer dumps all of the old files into the a folder named "Windows.old". In the end, the PC steps seem to be the most painless (unless you're a millionaire!).[/citation]
I have a friend who was a big fan of Ubuntu switching from XP (he probably still is). After a few years, he switched to Win7 some months ago.
My personal experience was, I boot Ubuntu up, couldn't get my wifi setup properly. Then I gave up. Call me dumb if you want, but I simply didn't have time for that.
Ubuntu is nice, but it is not to the point suitable for mass adoptions yet. I will wait until that time come. For some, the above picture still applies somewhat, except it is exaggerated of course.