I hope someone can help!
My daughter downloaded something (no idea what

) she said when she clicked on it and extracted it music started playing, she closed all programs down but it carried on so restarted it to stop it.
On restarting there is just a black screen although the windows Explorer box opens automatically and files can be opened through this.
There is no desktop though so cannot get to system restore as there is no start menu.
I have tried to start in safe mode but get the same black screen with no desktop, have also tried to start using last known good configuration but still the black screen
the operating system is Vista
Anyone have any ideas what is wrong?
Thanks