Margaret, a virtual machine is a program you instal that pretends to be a computer"within" your computer. The benefit is that it can run any other OS within it. So you can have a windows XP "computer" running within win 7. Thus you could have your picture it program running on XP within your new win 7 laptop.
I use Oracle Virtualbox
https://www.virtualbox.org/ at work to practice stuff on so I can't break anything real. In my case I run a Linux virtual machine on my works windows laptop.