This is 10i report not 11g.
Since you have no experience on reports,
I will try to give simple way...
Open the .rdf file in report builder.
Go Data Model
In query- in select statement include the 'description' column such way that query will work as earliers.
Once above line is confirmed, go to layout, click filed from toll bar,
Click F4 -> select the correct 'description filed name' and keep this filed on layout as per required place.
Now save and run the report, it should work atl east...