Different printer drivers is often the root cause of this problem. Printing to the same printer, if you are using different versions of Windows will use different printer drivers. Even in the same version of windows, if they have different versions
of the same printer driver, there could be differences.
Try installing a generic printer driver, like a 3rd party PDF generator, on all of the machines. See what happens.
How to trouble shoot printing problems in Word 2010, Word 2007 or Word 2003
http://support.microsoft.com/kb/826845
http://support.microsoft.com/kb/826862 - 2003-2007
http://support.microsoft.com/kb/291344 - 97-2002
How to install a TEST printer driver
http://www.pptfaq.com/FAQ00952.htm