Hi Brian,
There was probably software that came on a CD with your
scanner. The most common such program is Text Bridge
by Xerox, I think all of my scanners came with it. Look
in your Program Files for folders beginning with "Text Bridge".
Text Bridge will convert from files like you mentioned TIFF, GIF, JPEG .
When you scan the document you might want to try it a
few times to see which gave you the best results. You will
find the vertical alignment is very important as are controls
for contrast and brightness. Use the maximum DPI that
the software says it can handle, it may not be much higher
than 300 dpi. Looks like that is probably covered in the
topic "Scanning" in the document Trevor suggested
(which looks good).