This comes up because my wife and I just ran through the entire run of "The Office" on DVD. I'd seen seasons 1-5 before and most of 6 and 7, but never the full 1-9. I am comfortable at this point saying that it's my favorite TV comedy ever, and Michael Scott is my favorite TV character. He's a perfect idiot-who-means-well. Season 1 is a little slow but by the 4th episode of season 2 the show consistently kills.
Other favorite TV characters are George & Kramer from Seinfeld, and Phil Dunphy from Modern Family.
MoFy lost its luster for me after the first couple seasons but I really enjoyed those early ones.
Seinfeld is historically great to me as well. My #2.
What is your favorite?