This is probably not what you wanted to hear/read, but there's a reason why fsck behaves this way.
Even if the -a -A (-p -A) options are set (they probably are), fsck will ask you to make choices if it's 'confused'. The use of the -a (-p) options is regarded as 'dangerous', although just about every distro uses it.
If your system gets to the point where it cannot repair the fs by itself, it's not a good idea to ignore this and (try to) mount partions. Depending on the errors that surfaced, you will have a very unstable (disk)situation on your hands and (unrepairable) errors may be the result. Worst case: 1 (or more) partitions become unusable.
If you still want to walk this path, take a look at the fsck script and reprogram the part that handles the errorhandling (please don't......
Hope this helps.