Episode IV. That's my hill.
NeuTrek. TNG squeeks by, but any Trek with a dysfunctional, corrupt Federation with a Black Ops team is out.
The West Wing, season 4. After Sorkin left it went to shit.
Ren & Stimpy was hit or miss, but really after the first season it fell off a cliff pretty fast.
Nobody's ever done an adaptation of Asimov's The Foundation Trilogy, which is too bad.
TLoTR had 3 movies; everything after has been just a shitty job of milking the success of the first 3. Which is too bad, because Cumberbuzzle was brilliant as Smaug.