Crystal Report takes too much load time

Hello ,
In Windows Application, I hv to show 1 Lakh Records in Crystal Report at a time (these Records comes after all where condition in SQL).

Filltable (ds.Tables["DataTable"],SQL);
CrystalReport1.SetDataSource(ds);                           crvReportViewer.ReportSource = objCrystalReport1;

All coding lines executes with in 25 Sec.
After that Report takes too much time to show Report.

What could be the cause ??

I have not included Subreport, Page N of M .
Only Grouping , Summary field are there .
Report does not come after 1 hour in PC with Win7 with 4 gb RAM & SQL 2008.

Also I can't debug the application bcoz all lines executes successfully.

Is there any way we can show partial pages from all data ?

Regards,
Yogesh