Geog help :)

In retreat glaciers can still have an impact on the landscape although not in the normal way. Their energy is reduced (but they don't go backwards!) so all that happens is that they still continue to erode their valleys, but only up to the edge/snout of the active glacier. The activity will however, be concentrated at higher altitudes than previously. There will also be shrinkage down (ie the sides will not be as high.) - this might have an impact on valley shape and tributary glaciers.
They will, however, erode in a very different way ie with meltwater - this is generally increased in glacial retreat circumstances, consequently outwash plains and morainic material is transported and deposited in a fluctuating manner. So I would look at Fluvio-glacial topics to help the latter part of your question.