I'm also running XAMPP on a Vista Home Premium PC.
1) I downloaded my XAMPP zip file from apache friends
2) I unzipped it to the root folder on my D: drive, but it can be any drive and any folder "in theory"
3) ran setup_xampp.bat and followed the prompts to confifure my XAMPP
4) ran xampp_start.exe in the XAMPP root folder and it started Apache, MySql. They and PHP work fine
There is a readme.txt in the xampp root folder with instructions on how to install and configure xampp. It should be straight forward.