A short salutation is an act of politeness. Even if the internet is an virtual area, there is always a human being behind the screen. A polite beginning helps to get polite answers too. Please keep that in mind if you start a new thread.
Capt_Frodo wrote:What can I change to make him be redirected to the wiki folder when he forgets to add it to the end of the URL?
The easy way would be to modify your \xampp\htdocs\index.php file. This file contains already a redirect to your \xampp\htdocs\xampp\ folder which you can change to your wiki folder. This will affect your own requests too so that you have to add /xampp/ to your url too if you want to access the orange XAMPP administration page.
The other possibility would be to create the redirect based on the $_SERVER['HTTP_HOST'] value so that you can distinguish if the request goes for localhost or an ip.