You don't mention whether you did an on-line virus check - the TrendMicro or maybe (my preferred) the Norton one. But I'd guess you did or have an updated AV loaded.
And a scandisk/defrag might help.
Did you try an uninstall/re-install of IE?
It probably would be useful to know what processes are running when the freeze occurs (assuming the keyboard doesn't lock up too).
What other programs are "not responding"?
amowf
nb: What do you mean by "Script Engine re-loaded" ?