I tried to learn Dvorak keyboard layout a few years ago, and got reasonably good at it, but I couldn't get past the fact that command-key shortcuts were no longer in the right place.
In particular, Ctrl+Z (undo), Ctrl+X (cut), Ctrl+C (copy), and Ctrl+V (paste) are all chosen specifically because of the location of those keys on a Qwerty keyboard (well, maybe Ctrl+C makes sense). Ctrl+A (select all) and Ctrl+S (save) are also very convenient because of their Qwerty keyboard location.
Is there any way (on Windows XP) to use Dvorak except when a control key (Ctrl, Alt, and/or WinLogo) is pressed? (Preferably without having to install any third party app.)