#1 The Satan Pit episodes are what gave me hope for the show. I struggled through the series until those episodes.
Anyone who says the new Who isn't proper sci-fi should watch that episode.
#2 Utopia/The Sound of Drums/ Last of the Time Lords: I was at the edge of my seat watching these and didn't go to bed until 1am in the morning when I had to teach at 8:30 am.
#3 Human Nature was/ Family Blood was great. Even my fiancee was sitting down to watch it...mind you the questions wouldn't stop.
#4 Silence in the Library/Forrest of the Dead: I thought it was a great episode.
#5 Blink: Don't need to explain why this episode was awesome.
#6 The Sontaran Stratagem/Poison Sky: I love the Sontarans.
#7 Bad Wolf: Probably my favourite Season 1 episode.
#8 Tooth and Claw
#9 Turn Left: I know it was a filler but I liked it.
#10 Doomsday: BECAUSE ROSE IS FINALLY GONE!!!!
As much as I love new Doctor Who I could also easily come up with my top hated episodes. 'Love & Monsters' anyone? So so very bad.