Uninstall Applications under Win7 save mode

You need to edit the registry to allow the windows Installer Service to run under the save mode in order to uninstall applications.
Save mode Registry key:
Right-click on Minimal
and select New -> Key
Name the key MSIService and change the default value to Service by double-clicking it

Networking Safe Mode Registry key:

After boot into the save mode
run the following command:
net start msiserver