Hi,
with LV 5.1 you can use the activeX library of Excel and Word to create reports.What you need is to know the related methods and properties. As an example take a look at Write Table to Excel.vi in the ActiveX examples.
Anyway I would suggest you the LV Report Generation Toolkit for Office, see here: http://sine.ni.com/apps/we/nioc.vp?cid=5769〈=US.
Unfortunately ,as far as I know, it is only available for LV6 and LV6.1, then an update is necessary.
But believe me, I've been using this toolkit since its release and I can say it's definitely worth the price!
Good luck,
Alberto