Applications don't crash Windows much anymore. This was a problem in years past but MS got their act together and protected the core system processes from stuff like this. Blue screens these days are almost always caused by one of two things: damaged system files and bad hardware drivers. Since it seems to be Opera thats triggering the event I would bet that it is, ultimately, a driver issue. Check your event viewer and track down the logs for the crashes and post them here.
Also, are you the same as the OP? You have a different account name...