A general queston about sending errors to Microsoft??

Hi all

I have been reading the threads and this has been coming out in a few of them about sending the error messages to Microsoft,I have seen these on my computer and have always clicked don't send.Are these important to send??Main reason I don't send part paranoia and part don't understand why we need to send them.

I know its not technically NIS problem but would involve NIS/Norton if their program was involved.Thanks for your opinions.