The fact that En started OK in the new profile is good. You can now delete the new user account that you created.
In Vista, Encore's app data folder is here:
C:|Users|[your account]|AppData|Roaming|Adobe|Adobe Encore|4.0
Rename the folder then launch En again. It should start normally for you.
-Jeff
The Focal Easy Guide to Adobe Encore DVD 2.0