Two things to try here (Both work in Word 2002 but you`ll have to check Word 2000)
In Word go TOOLS > CUSTOMIZE > COMMANDS tab and leave this in the foreground. Click on the menu bar TOOLS so that the menu drops down. Now drag the offending entries off the tools menu. Close the tool menu and then close the Customise dialog box. This works in Word 97 so it do the trick but I don`t know why they keep recreating.
Does Word 2000 have a DETECT & REPAIR option under the HELP menu? If so this might be an option.