Sure thing, Cindy. Unfortunately, .doc commands (what Word creates) don't automatically translate over to HTML (what this vBulletin creates.) You have two options to get it to work properly, but both are a bit of a pain. You can:
1) Cut and paste into the window and then use the cursor to go to the first letter of every new paragraph, backspace to remove the .doc hard return, and substitute it with an HTML return (just hitting your Enter/Return key to reinsert the line will do it automatically); or
2) Use Word's Find and Replace function to remove each hard return and replace it with <p> (the HTML paragraph command.) Up through Word 2005 (and possibly beyond, but that's what I've got) here's how you search for paragraph codes:
a. Click on "Edit"
b. Click on "Find"
c. If it's a short box, look for the word "More" and click it.
d. If it's already a long box (you'll see a list of "Search Options" if it's long), or after you do step c., click on "Special"
e. Select "Paragraph Mark". You'll see a ^p appear in the Find box.
f. Look for the top tab marked "Replace" and click on it.
g. Enter <p> in the replace box.
h. Click "Replace All"
Once that's accomplished, it'll appear weird in Word, but when you move it over here and paste it in the window, it'll show up just fine when you Submit Reply.
Hope that helps!