Wndoows 7 Disk Read Error

[chevyboy55]

My daughter called today & said her laptop (Dell XP with Windows 7) is getting a disk read error. She said she was watching a Netflix movie (I'm not sure if it was a DVD or streaming) & had a recipe window open when she got the error. & It said to hit clt,alt delete to reboot. The problem is that does nothing. I had her try to put the installation disk in & boot up hitting the f8 key but it gives the same message. Any ideas on where to go next?
Come to think of it I think she has Vista not Win.7