I know what you mean! I skipped Word 2000 from Word 97 to Word 2002 and in the latter it is very annoying. Does the clipboard icon appear next to the pasted text in 2000? If so there are options from there to adopt the formatting of the original document or the current one.
However, in my experience it is far easier to copy and paste everything and format text last. If you use the same font for the whole document CTRL+A selects "All" the document and you then select the requisite font. Take a look at the format painter icon (It looks like a paintbrush)in the help files. Place your cursor in a piece of text whose formatting you want to copy, click the icon and then drag the cursor over text you want to have the same formatting. In tables you can select whole rows, columns or individual cells. Double click the icon and you can format multiple sections - but don`t forget to turn it off by clicking the con again or pressing ESC key.