The mood is something that changes slowly, and can keep us good or bad company for hours or days; its reasons are deep inside us.
An emotion is usually raised by a stimulus that triggers our feelings, this stimulus
could even be internal, from a memory, and therefore brought us by the mood.
Emotions don't last for a long time, as they absorb all our mental energies, I believe a very long duration for emotions could be even dangerous for surviving.
A mood (unless in pathological situations) be it bad or good, allows us to care after daily matters, but could trigger sudden emotions.
Emotions have a short duration, but can be regenerated, with the same intensity, under similar circumstances.
The same strong stimulus, if we are in different moods, could lead to
different or even in some way opposite emotions, for example, deep empathy or fear.
Emotion are one of the key facts that make us take decisions, and therefore prepare our path in life, therefore are (at least partly) in control
of our future moods.