The events that involve the Creature are certainly crucial to most of the plot of Mary Shelley's novel.

1. While his creation is momentous, Victor's mad rejection of him is of equal magnitude.
2. His murder of William Frankenstein which begins his path of vengeance
3. His discovery of the DeLacey cottage affords him the opportunity to observe human interaction and love. From the DeLacey's he also learns to speak and to read.
4. His readings of the classics, especially Paradise Lost, affects the Creature deeply as he perceives himself in similar situations to Satan, who is rejected by God and Adam, who is without a mate.
5. His confession to Walton and his angst over Victor's death.

I agree with lentzk: there are far too many to limit the important happenings in the life of the creature.

Here are my suggestions:

1. The creature is given life.

2. The creature is abandoned.

3. The creature learns about life and his origin.

4. The creature searches for companionship.

5. The creature looks to Victor for forgiveness.

There are almost too many to list, so I narrowed it down to five events that feature the creature's issues with Victor's abandonment of him and his desire for revenge.

1. He murders William, Victor's younger brother, out of revenge for Victor abandoning him.  He's really, really bitter about that decision.

2. He meets the compassionate cottage people who show him the first kindness he has ever experienced. 

3.  The creature reconnects with Victor in Switzerland and asks him to create a female creature as a companion for him.  He really just needs a friend.

4. The creature waits with anticipation for the creation of his 'mate,' only to discover that Frankenstein has destroyed it at the last minute.  The creature swears revenge.

5. Creature kills Elizabeth on Victor's wedding night.  Now Victor is as alone and desperate as the creature.