I have found with Explorer (Version 6.0) open and I open Word (2000) often times Explorer will freeze with the Message Internet Explorer has encountered a problem and needs to close . . .
If Word is first opened then opening Explorer can cause Word to stop responding with a similar message regarding Word.
I have lived with this problem for years on one machine at home.
It's always a roll of the dice if I want to work with Word and Explorer both open.
afinepoint