Hi Ashwin Raj,
I am answering to your first question here.
When you are prompted to give a name, the name you enter will be the "Form Library" name at sharepoint site.
When you are publishing a form to SharePoint, it picks up your InfoPath solution(".XSN") and stores it as template.xsn(It does not remember the existing name of your InfoPath solution.
So When you click on "Fill Out a Form" at sharepoint, sharepoint site will open the template.xsn file in your form library. The Xml file that is generated when you save after filling the form will point to the 'template.xsn'(for ex.
http://system/sites/ExpenseSubmitter/Forms/template.xsn) at your sharepoint site. You can see the href by opening .xml file in notepad.
Hope this helps!
Agni
InfoPathDev India