This should do the trick.

NOTE - registry edit so please backup if not sure what your doing

This will get rid of the preview option thus leaving OPEN as the default action


1. Run the Registry Editor (REGEDIT.EXE).

2. Navigate to HKEY_CLASSES_ROOT\ SystemFileAssociations\
image\ ShellEx\ ContextMenuHandlers.

3. Delete the ShellImagePreview key.

4. Close the Registry Editor when you're done; the change will take effect immediately.

Thanks

Richard