Do LMB fingerlings, say from 2 - 5" long prey on young of year BG hatchlings when they emerge from the eggs?
Yes, in most ponds YOY BG most likely make up a fairly high percentage of YOY bass diet, along with other YOY fish species present and larger sizes of zooplankton.
Another question:
What do red eared sunfish feed on in lieu of mollusk?
Invertebrates(water fleas, insect larvae, scuds, etc) including zooplankton, often those that relate to the pond bottom where RES are most often found.
Will they feed on minnows and crawfish young effectively...
RES are not effective at preying on minnows, but will opportunistically feed on them. They are more effective at feeding on YOY crawfish.
and will they also take pelleted feed?
RES do not take to pelleted feed nearly as well as BG. However, they often take feed that has sunk to the bottom and some forum members have had luck hydrating feed and getting RES to take it. A few RES may adapt to taking floating feed, but that is far from the norm.