My students always want a recommendation on what software to use and for the beginners and the advanced students, Lightroom is the answer! It is designed for photographers and just works incredibly. It is intuitive to the way we think so beginners can grasp it easily to create wonderful images but capable enough for the seasoned pro to maximize image potential.
Here is an example clip from the good folks at Adobe and Adventure Photographer Tyler Stableford:
And here is Adobe evangelist Terry White demonstrating his top five new features in LR3: