MS Windows 98 is a retail OS. this can not be legally shared or offered for download. you can most likely pick up a copy of this on ebay.com or http://recycledsoftware.com/
Please search the forum, as these requests have been answered before. Oldversion.com only deals with Freeware and Shareware apps.
Originally posted by FAQS@ http://www.oldversion.com/faq.php
Why do you only have freeware and shareware?
This is not a "warez" site. We are able to legally distribute only freeware and shareware, since they are free.