Try installing another launcher. Then press the Home key and it will ask you which launcher to use. Select the "new one". Then try going in to Settings -> Applications -> Manage Applications -> ADW and Clear the data.
You will probably also want to delete the "settings backups" that are stored on the sdcard, if you created them.
Then you should be able to switch back to ADW.
If you can't get to the market to install another launcher, you will probably have to side load i using ADB.
Or as Lie Ryan suggests, use the Market Web interface to install another launcher.