Windows XP problems?

Well here's what happened...i went on my dad's laptop. I did nothing except for go on aim and read a pdf file for school, then i turned the laptop off. when i turned it back on like 5 minutes later, i have this problem. there is some kind of error and i have to choose from a list of things (safe mode, safe mode with networking, safe mode with command prompt, last known good configuration, start windows normaly) to choose from. i choose one then 5 seconds later, a blue screen with white text pops up for a split second, too quick to read, and then the laptop seems to reset itself, going back to that list of stuff (safe mode, safe mode with networking...)!! and this happens with ANY choice i choose! even safe mode! its like some kind of infinite loop! my dad is going to kill me when he gets home and i didnt even do anything to the dumb laptop, it just wacked out on its own! someone with extravagant computer knowledge please help me!