Print Page margin Setup in RDLC Reports...

 PageSettings ps = new PageSettings(); //Declare a new PageSettings for printing
                    ps.Landscape = false; //Set True for landscape, False for Portrait
                    ps.Margins = new Margins(47, 43, 149, 1); //Set margins
                    //Choose paper size from the paper sizes defined in ur printer.
                    //Here we use Linq to quickly choose by name
                    ps.PaperSize =
                        (from PaperSize p
                        in ps.PrinterSettings.PaperSizes
                         where p.PaperName == "Legal"
                         select p).First();
                    //Alternatively you can set the paper size as custom
                    //ps.PaperSize = new PaperSize("MyPaperSize", 100, 100);
                    reportViewer1.SetPageSettings(ps);

Report Dynamic File name while saving into PDF/word/excel

this.reportViewer1.LocalReport.DisplayName = "Report Name";