You might want to try WAMP
Install PHP 5 Apache MySQL on Windows : WampServer
I usually do my web development on Linux, but a few weeks ago I needed to take what I was working on (Joomla with VirtueMart...can't recomend it
) with me, and only had my TabletPC which runs WinXP TabletPC edition (more or less the same as WinXP Pro).
Wamp was just a straight forward install. Then start wamp, and everything worked. Apache, PHP, MySql, phpMyAdmin. I don't think WordPress is that different, so it shouldn't be a problem.
Edit: I use Wamp while using Skype, with no problem.