What's everyone's favorite episodes? Here are mine:
1. Blink (Season 3)
2. Silence in the Library/Forest of the Dead (S4)
3. Human Nature/Family of Blood (S3)
4. The Pandorica Opens/The Big Bang (S5)
5. The Girl Who Waited (S6)
6. Asylum of the Daleks (S7)
7. Day of the Doctor (50th anniversary special)
8. Father's Day (S1)
9. Doomsday (S2)
10. The Doctor's Wife (S6)
11. Time of the Angels/Flesh & Stone (S5)
12. Dalek (S1)
13. Vincent and the Doctor (S5)
14. The Snowmen (S7)
15. The Eleventh Hour (S5)
16. Bad Wolf/Parting of the Ways (S1)
17. School Reunion (S2)
18. Midnight (S4)
19. The Stolen Earth/Journey's End (S4)
20. The Impossible Planet/The Satan Pit (S2)
The first five or so stay pretty much the same; the other ones tend to move around on the list depending on the mood I'm in on a given day.
I love nearly all of Season 5, and honestly the top 10 could just be all S5 episodes, but that would make for a boring list to read!
Special notice should go to the mini-episodes "Time Crash," featuring a meeting of the Fifth and Tenth Doctors, which--if it were a full episode--would easily be in the top 5; the inventive short "Space/Time;" and the prequel webisode "The Great Detective," featuring Strax's immortal line, "I have declared war on the moon!"
As far as classic storylines, I was hoping to blend them seamlessly into this list at this point, but they're so different in tone, style, and even format that it's too much of an apples/oranges comparison. My current favorite classic serial is "Carnival of Monsters" featuring Jon Pertwee as the Third Doctor, written by the brilliant Robert Holmes.
So, what are other people's favorites?