You may get a borring boot of vista start on boot camp. Looks like vista can’t find the boot disk and find find find, this may take you 2 min to check.
Ok, now I get away from it.

  1. find you Vista install disk and boot from it
  2. choose fix instead of install
  3. open terminal and input bootrec.exe /fixmbr
  4. input bootrec.exe /fixboot

Restart!