Hi Wesley,
Bursting reports the way you need it will require you to make some changes to the report definition using Report Studio (ReportDesigner). That includes bringing in the group or user definition that you want the burst to be based on as a burst key.
I assume you are on a pre-2008.2 version, so you are probably on Cognos ReportNet1.1, there is some information in the Report Studio user guide that you might want to look into.
Following are some screenshots from that document.