If it boots into safe mode without crashing then it may be a program loaded on start up thats causing the problem. one way of finding a possible culprit is to stop all programs in startup found when you run msconfig from the run command. If you disable all and it works then re enable a couple at a time until the crash happens it must be one of the ones re enabled.
Another place for clues is the event viewer type eventvwr into the run command and have a look at anything with a red circle and cross through it. double clicking on an item gives more detail.
any program identified could be uninstalled and reinstalled to cure the problem
My money would be on Macaffe or Symantec anti virus programs which dont like changes of memory,
Rickity