At first this was just something I said when some friends repeatedly wanted us to watch NCIS. I said to my boyfriend: "I bet there is one TV show for each letter of the Alphabet I'd rather watch.
So here is my list:
A
ALF - I always watched it, when I was younger.
Ally Mc Beal - Alas I have never seen the end of it.
Angel - I think this would be my actual favourite in this category.
Atlantis - See Stargate.
B
Babylon5 - Decent sci-fi show.
Battlestar Galactica (New Series) - This is one of my absolute favourites.
Buffy - Hard to decide which I like more, Buffy or BSG... so I guess this makes two for B
C
I actually don't have a show with C I watch regularly or have watched in the past.
I have seen a few episodes of the following three.
Charlies Angles - Some time ago, well. I would probably watch something else before this.
CSI - I just watched an episode today, I am just a bit confused with all the spinoffs.
Charmed - I know that many people who liked Buffy also liked this, I however don't find it that special.
D
Dawson's Creek - The only show with D I watched more than once. It was alright I guess.
Deep Space Nine - Yes, I have listed it under Star Trek as well. Bad girl!
(actually in German we would have House here, as it is called Dr. House there, but as my blog is in English, I will leave that for later.)
E
Enterprise - Not as bad as some said. Not worse than the end of Voyager....
And if anyone says, that this belongs to S, as in Star Trek... If I had to, I'd watch George Clooney in
ER.
F
Friends - definitely Friends. "We were on a break!"
Firefly - Alas there isn't enough of this show to judge it against Friends.
Farscape - or the prequel to the later Stargate SG-1?

The series was great, but the end... no, I did not like it, it felt rushed... Like trying to find a quick solution to the problem of the open end...
Full House - This was good, when I was about 12 or so...
Futurama - I am not a big fan of these type of show but if any, then this one, I guess, or South Park?
G
Galactica - now that's cheating, isn't it?

But it gives Buffy the B-spot.
H
Hercules - I always connect this show with Latin homework. Probably because it was always on on Sundays and I waited for the last moment to do my Monday- Latin-Homework.
House - I like the humour and it is the only medical series that's not boring.
I
I??? I've never heard of any of the shows listed here:
http://en.wikipedia.org/wiki/List_of_U.S._television_series#I
J
JAG - This was on after Voyager for some time.
Joey - Not a brilliant as friends, but decent enough.
K
King of Queens - Quite alright if you need something to laugh.
L
L-Word - The same friend (or one of them) who wants us to watch NCIS also brought along this show. What shall I say. Love it or hate it.
Lost ??? - I must confess I have not seen it, yet. And I don't feel like just jumping into it, in the middle of the show. I have to rent the first season, I guess...
M
Magnum - Sexy man, at least that's what I thought a while ago. He's still alright, I guess.
N
Well, here we are, NCIS category....
NUMB3RS - I have seen about two episodes. I like it, especially since it has a lot to do with the stuff I learned at university. I'd watch more if I had the time. But there are other shows higher up in my priority list.
O
SKIP
P
Prince of Bel-Air - I love Will Smith!!! And yes, I cheated again, it is originally called The Fresh Prince of Bel-Air but not where I live, so... F was full anyway.
Q
Quantum Leap - Hello Captain Archer. Well this show is quite old-fashioned, but ok...
R
Remington Steele - I also love Pierce Brosnan.
Roseanne - Long time ago, but yes, I watched that too.
S
Star Trek ... - Oh I love TNG (Data and Riker and... well all of them), I hate Kirk, I love Sisko without hair and Janeway, well not a big fan of her and don't like her hair at all!
Stargate ... - I love O'Neill and Daniel Jackson, and Atlantis is alright too, my favourite there is Rodney McKay.
Please count Stargate SG-1 as I might use the other shows at A, D, E, T and V.
T
TNG - see Star Trek.
24 (Twenty-four) - I LOOOOOOOOVE this show, unfortunately I have to watch this alone, as my boyfriend gets too nervous when watching it. So I always tape it and watch it all in one go (using headphones), when he's busy, but he keeps asking what's happening so I usually tell him all the events of 4 hours in 15 minutes.
U
nope
V
Voyager - Decent series except for Janeway's hair and the finish...
W
Witchblade - I have only seen one episode as I never figured out if the show even made it to German television.
X
X-Files - Mulder and Scully, they are something...
Xena - I have not seen this as often, I preferred Hercules.
Y & Z
I had two for X so don't complain!