Files received via the ILL e-mail option (once properly decoded) are in
TIFF format, specifically CCITT Group 4 TIFF format.  Here are some 
ways to view and print out this information. 

On Win95/98/ME/NT, the twisty path to follow is:

Start -> Programs -> Accessories -> Imaging

On Win95, the program is called Wang Imaging and is usually found in
c:\windows\wangimg.exe.

On Win98 and WinME, the program is called Kodak Imaging and is usually 
found in c:\windows\kodakimg.exe.

On WinNT, the program is called Wang Imaging and is usually found in
c:\Program Files\Windows NT\Accessories\ImageVue\wangimg.exe.

*****

On unix, some programs show only the first page of the TIFF and
others (xnview) show all pages but cannot convert to something useful
(like postscript).  So far, the easiest thing (I've found) to do is to get 
and install the free libtiff utilities from http://www.libtiff.org.  One of
the utilities is called tiff2ps, which called in the following way

tiff2ps -ap FILENAME.TIF > blah.ps

will convert the file into viewable (gs, ghostscript, gv) and printable
postscript.  Warning:  the files that tiff2ps generates are large.  In my
test, a 1 meg TIFF file became a 40 meg postscript file.

*****
 
For the mac, there are two shareware programs: ImageViewer 
(http://www.imageviewer.com) and GraphicConverter (http://www.lemkesoft.de) 
that will display and print TIFF files.  The latter one will display and
print during the trial period, the former will only allow displaying until
the program is registered.