Using CRVS2010, you can remove the unwanted export option.
The new CRVS2010 feature is the ability to change the available export formats from the viewer's export button. The following C # code example demonstrates how to configure CrystalReportViewer to export only to PDF and Excel file formats:
int exportFormatFlags = (int)(CrystalDecisions.Shared.ViewerExportFormats.PdfFormat | CrystalDecisions.Shared.ViewerExportFormats.ExcelFormat); CrystalReportViewer1.AllowedExportFormats = exportFormatFlags;
See the link below for more details.
http://scn.sap.com/community/crystal-reports-for-visual-studio/blog/2011/01/26/export-file-formats-for-sap-crystal-reports-for-vs-2010
source share