How to disable Cacheman?

Activate the Settings Page. Click on the Preset menu and select the Disable Optimization menu item. Click on the File menu and select Exit. Answer the Save Settings dialog with Yes. Answer the Reboot dialog with Yes.

Is there a way to restore the pre-Cacheman settings from the dos prompt?

On first launch, Cacheman backups the system.ini file located in your windows directory to "c:\yourwindowsdir\system.cam". Copy the file back as system.ini to restore your original Disk Cache settings.