My windows will not start in any mode

Whhhyyyyy? Sob sob. It was working fine yesterday but when I woke this morn and turned on my comp (emachine) it went to the screen where it's asking so I want to start it in safe mode or normal mode etc. The thing is it won't start in any mode. what should I do. And my comp came with xp installed without a disk.

Hello,

Your Windows files are corrupted. Do you have your XP disc? We need to perform a repair of the OS.