personally, mine would have been quite different

1. Entering Diagon Alley (PS)
2. First sight of Hogwarts (PS)
3. ‘He doesn’t need protection the Dark Lord is gone’ (DH/2)
4. ‘You have your mother’s eyes’ (DH/2)
5. Snape kills Dumbledore (HBP)
6. ‘Yer A Wizard, Harry’ (PS)

I could do this for hours and make a total top 50… but that would be a large waste of time