How does one generate vertical quotes in Word?

When typing, right after you type a regular double-quote, if Word turns it into a "smart quote," immediately hit Ctrl+Z. This should undo that automagic change. This distinctly works in Word 2007; I just tried it to be sure.

It depends which version you are running as to where this is, but you can turn off this behaviour. Uncheck the following option:

Tools / AutoCorrect Options / AutoFormat / Replace / "Straight Quotes" with "Smart Quotes"

In Office 2007 you can change the formatting that Word does automatically through the main button on the ribbon.

If you want this behavior changed permanently: Under Proofing > AutoCorrect Options > Autoformat as you type... You can de-select Straight Quotes as Smart Quotes and that should revert the quotes to being straight.