Windows not booting

[Ety]

My Stepdad has to turn my PC off the second I walk away from my PC and he turned it off last night and now Windows won't boot. It asks to select Safe mode, Last know working setup, and boot normaly. No matter what I chose it just resets the PC and the same thing happens. I tried to boot of 2 disks of Knoppix I have and it wouldn't let me boot of them.(Yes they are set as first boot device) I had probblems last week of my PC randomly restaring and the time being off. I cleaned out the PSU and it fixed it. I am going to try cleaning out everything tommorow. Any ideas what happened? I can't find my XP disk and I think I'll just install Fedora. Can create a Partison for Linux without losing any of my files? I have 20+ GB empty on 2 partisons so I have plenty of room.

Thanks alot,
Ety