Thanks Dirk,
You have nicely give all answers of my questions. I will take care of your points while creating the sub-domains. Also, I received this message from Google after filing the reconsideration request:
Dear Webmaster of http://www.webstarttoday.com/
We have processed the reconsideration request from a site owner for http://www.webstarttoday.com/. The site has been reviewed for violations of our quality guidelines. Any manual spam actions applied to the site have been revoked or adjusted where appropriate.
As per the message my website should had revoked from the penalty but the penalty is still showing, under "Manual action".
Thanks,
Ruchi