Alex Netkachov has posted a new tutorial to his blog today about installing a custom LAMP setup (Linux - Debian, to be exact, Apache, MySQL and PHP) inside of a virtual machine.
Installing Linux is not a complex task, you only need to follow some instructions and have basic understanding of how computer software and hardware work. Also you should be ready that documentation will be different from what you already might have seen. It means that it may be less colorful, more technical, and have different terminology. That's Ok. What you need is only to follow the doc and try to understand it - like thousands of people.
Most of the post is taken up with installing the Debian instance inside of a virtual instance (he mentions three, they're all about the same - VirtualBox, VMWare Server and VirtualPC) and includes a slideshow of images to help you through the install process. Once its installed, its just a simple matter of a few apt-get commands and you'll have MySQL and PHP setup to work with the already-installed Apache instance.