The default server root (where your index.html and the rest lives) is /Applications/xampp/htdocs
You are now running a high-powered web-server on your desktop -- it would be well worth your time to get a book on Apache and learn about htppd.conf -- the configuration file for Apache.
I have 5 different sites set up on another disk partition -- nothing in the defalut 'htdocs' folder. All done with edits to the .conf file.
If you like contact me off-list (firstname.lastname@example.org
) and I can give you the details.