Install the FCK editor provider as used in this forum. Up there in the toolbar is a paste button with a W on it. That pastes from Word whilst stripping the extraneous styles. You can easily create your own toolbar and remove the other paste buttons if you want to reduce confusion.

There is also a button that removes all formatting and pastes plain text, but that will probably go too far for your needs.

The disadvantage of letting users paste formatted content is that it will override your set styles... meaning you'll end up with different fonts all over the place after a while.

Rob