If you want to send mail with table data then you can do it like this.
1) bind table to gridview
2) put gridview in panel control
3) and you can render your panel as html control ans send mail.
StringBuilder SB = new StringBuilder();
StringWriter SW = new StringWriter(SB);
HtmlTextWriter htmlTW = new HtmlTextWriter(SW);
pnlDetails.RenderControl(htmlTW);
string body=SB.ToString();
replace your panel id to pnlDetails
now you can send your body in mail