Hi TimmyJ,
Dont you wish she had just left it alone for another few minutes to finish, It does say do not turn PC off in big letters...lol
If you boot the VistaDVD and select System Restore you will be able to access that Restore Point you created
This Tutorial will be able to help
System Restore - How to Just follow Method 2 and the Video
Every VistaDVD has these options, You will be able to use it to restore the system
Let us know how you go
Steven