How to uninstall Reporting Services on SQL 2008 R2?

From SQL Server Reporting Services(SSRS) 2008, the SSRS is Internet Information Server(IIS) independence. This means there is no directory for Reporting Services under IIS.
In this case, please make sure the SSRS service is running, otherwise, we are not able to configure the Web Service URL and the Report Manager URL(means configuring the virtual directories).
Anyway, in order to uninstall SQL Server Reporting Services without uninstalling other SQL Server components, please follow this guide:

1. In Add/Remove programs
2. Click the 'Uninstall/Change' button for "SQL Server 2008 R2"
3. In the coming dialog, click 'Remove'
4. Click 'OK'
5. In the 'Select Instance' dialog,  select the appropriate instance, and then click 'Next'
6. In the 'Select Features' dialog, please only select 'Reporting Services'
7. Then click 'Next' and 'Next' till the uninstalling process starting