I found a solution to implement this functionality by modifying the web.config file as under:
<mailSettings>
<smtp deliveryMethod="SpecifiedPickupDirectory" from="Your Name <
[email protected]>">
<specifiedPickupDirectory pickupDirectoryLocation="D:\emails"/>
</smtp>
</mailSettings>
inside the system.net settings
This displays the "Complete" step of create user wizard and saves the email in local folder "D:\emails" instead of sending them by smtp.
If any other method kindly let me know.
Thanks.