Please, please take out the recommendation to disable UAC when XAMPP is installed in Vista. Recommending a different folder is fine, and you can even tell them how to change permissions of the XAMPP folder.
But please do not recommend disabling UAC. You're asking people to remove a layer of security that could protect them from malicious software.
Also, I looked at the "interactive" HTML tutorial recommended by XAMPP - it's pretty out of date. It's an old tutorial from back in the early days of the internet, complete with horrible formatting and filled with ads. A lot has happened since then.
CSS layouts are the norm now, and AJAX and other "web 2.0" technologies are coming in quickly. For learning about today's web technologies (including basic HTML), I'd rather W3Schools be recommended instead.