Have you tried looking up the STOP code, on support.microsoft.com ? You can find this code in the System Event Log (in Event Viewer) logged after the restart as "the previous system shutdown was unexpected". There should also be a link in the message like "For more information, see Help and Support Center ..." - try that and see if anything comes up.
There are too many kinds of crashes, and causes of crashes, to make any kind of diagnosis from "it crashes"... because it happens while you're in IE does not guarantee that IE is the cause.