Windows XP? What's that? The last Windows I owned was Win98. Didn't care for it at all. It was what drove me to Linux. Both PCLinuxOS and Mepis will be releasing distributions with KDE 4.4.0 in the very near future. (I think PCL will probably put out an RC in the next couple of days.)
It has been said that KDE has a look and feel closer to Windows than other window managers, but I have a feeling the 4.4.0 will be a couple of giant leaps beyond the current Windows.
Of course there will be a learning curve. When people tell me it's too hard to learn a new system I keep wondering how they managed to learn Windows in the first place. I don't think we're born with innate knowledge. The best method is, "Learn by doing." And, once you start "doing" there's plenty of How Tos and helpful people on the forums that will be happy to provide assistance.
Sadly, some people are fearful of doing anything on their own because they could "mess up" their install. This isn't a problem. The worst that can happen is that you must reinstall. And that's an easy chore in Linux. (You did back up your personal data before you started messing around, didn't you?
I haven't checked lately but I'm hoping Unity is getting close to a release. I'd love to have a brand new Granular in the very near future. . . . Like tomorrow.