i think the vista disk you have has some problems. you can either try cleaning the disk (some alcohol based liquid but don't use clorox, etc) and try rebooting the dumb thing again or borrow vista or windows 7 (preferred) CD from your neighbors/friends if possible and reboot. make sure you format the partition that contains your system software (usually drive c) but you'll lose all files except the ones you stored in other partitions (D, E.... whatever you have)
  ps: how are you booting it? do you start your laptop and insert the disc and follow the steps or do you go to BIOS? that might make a difference.