I figured out how to get the guest to stop on crash and not reset. From safe mode, I did:
Control Panel > System > Advanced tab > Startup and Recovery...Settings button
uncheck System Failure...Automatically restart > click OK.
I then let it boot normally and when it crashed I got the BSOD. I'll attach a screenshot, but for the benefit of search engines:
The problem seems to be caused by the following file: intelppm.sys
*** STOP: 0x000000CE (0xF88B58F8,0x00000000,0xF88B58F8,0x00000000)
Edit: a search for this error shows this ticket: http://www.virtualbox.org/ticket/420
. I'll try the workaround it describes and post my result. It might be an important data point that I exported this guest from an AMD-based system and imported on an Intel-based one, so it may well be related to the processor model.