virtualbox.org

I'm running windows 7 and have installed Win XP Pro in Virtual Box. I'm not a techy type at all. Can people explain clearly please, step by step, how I install and run a program in Virtual Box?
Cheers,
Peter.

You would install it just like you would install any other program. Just install it in the guest and not the host.
I suggest you do a fair amount of reading, starting with the VBox manual.