Depends on which version you use.
For 2004, you can just delete everything in your /Dispatcher/Downloads folder then delete the Dispatcher.chump file from the /Cache folder. 2004 on start will rebuild everything so you will only see default content.
2006/TC, I figure you go to the Installed tab in CMP and choose everything that does not have the yellowish computer icon that stands for default content. Delete it in CMP and you get nothing but default items.