The following instructions are for Office XP (Word 2002) but Word 2000 should be very similar.
Do a search for 'normal.dot' and double click it to open it in Word, it should be a blank page,
if it isn't ...
close Word >delete the file 'normal.dot' > re-open Word to create a new 'normal.dot'
then
With Word open > Tools > Options > Save > ensure the Default Save Format is Word Document (*.doc)
if 'normal.dot is a blank page you need to check the 'switches' on the Word 'Command Line' see
http://support.microsoft.com/default...roduct=wrd2003