I'm not really that familiar with VSD (have had it and played around with over the last 2 years a few times) but I believe you just need to locate your .vnu file and open it with the current version. I'm not sure about older versions, but newer releases store a copy of the .vnu file on your server when you publish. To check your current version you could do one of several things 1. open VSD, click on "Help" menu bar, select "About" and a dialog box will open telling you what version you are running. 2. Go to CoffeeCup.com site and select "Your Downloads" from the "World Class Support" menu at the top of the site, scroll down until you see VSD on your list and it should tell you if a newer version is available. Current version is 7.0 Build 18

You can verify which version of VSD (or any CC software for that matter) by clicking on help/about.
When you say you want to "transfer everything. . .back over to my computer" aren't the original files on your computer now? If they are then the updated program will do what it needs to "update" to the new version.
Hope this helps - a bit.

It sounds like she doesn't have any of the original files and wants to transfer all the files from the website to another pc.

The version is important - newer versions load a back-up folder with the site. If you don't have a back-up version, here's what you can do (rather than starting from zero) -
Create a new folder for your website. Go to your live website and "snag" all your photos and graphics (right click and save as), put these in your site folder. In VSD, open a new site and set up your pages. You might have to re-do your background if you don't have it saved anywhere. Copy/paste the text from the live site into text boxes on your VSD pages, insert your graphics and photos. It's not perfect - there may be some things you just have to do over, but it's better than nothing

Be sure to back up your new site files (external hard drive, jump drive...)

Visiting the location on your hard drive where VSD had saved the files before you removed it should prove helpful. Without VSD you cannot open your ".vnu" file, however VSD creates a folder on your computer called "websitename_website". If you open this "_website" folder you will find the raw HTML versions of all the pages you built using VSD, you will also find a folder called "files" which contains ALL the images created by or uploaded to your web site. If you no longer have these files on your computer, then simply open up your ftp site, browse to your root directory folder, save everything there, and copy back to your computer; this will give you basically the same thing as the contents of your "_website" folder. Hope this helps!