Forgot to add this, but I can't boot into safe mode. When I try, it restarts the computer automatically. This leads me to the virus conclusion. Also, it's an Acer computer. To do a backup, I need to load their eRecovery software in Windows first...which I can't.
As for a disk imaging program, I can't install anything more on the computer. I tried installing AVG on it go get any possible virus off, and the installer wouldn't load.
When it comes to a Windows 7 install, we got a free upgrade copy, so I could forget backing up Vista and rely on a Windows 7 backup disc. However, if it's a virus, it's just going to infect the new install, especially since 7 would back up the files on the Vista install.