If you are running XP or 2000, and you could somehow manage to boot into safe mode you could then right click on the My Computer icon and select Properties. Then in the System Properties window, select the Advanced tab. On that tab you will see Start up and Recovery. Click the button next to that.
A Start up and Recovery window will open. Mid way down you will see a section titled System Failure. UN-CHECK Automatically Restart.

Now if the crash occurs again you can read the stop error and then attempt to recover the system.

Or you could slave the hard drive to another Computer and recover the data, then reformat the drive and reinstall Windows.