The Report Viewer provides print report option in the toolbar to print a copy of the report. The page setup dialog allows you to set the paper size or other page setup properties. To see print margins, click Print Layout on the toolbar.
The values allow you to set in the Page Setup dialog box for current session only. When you close the report and reopen it, it will have the default values again. The default values for the page setup dialog come from the report properties, which are set in the design view.
The extra blank page is created when the Body of your report is too wide for your page. If you want the report to appear on a single page, all the content within the report body must fit on the physical page and the body width should be lesser or equal to the following formula:
Body Width <= Page Width - (Left Margin + Right Margin)
For more details on designing a report to remove the empty pages in the report, refer to the knowledge base article of report page sizing.