Calvin & Hobbes is my all-time favorite. For comics that are still published in my local newspaper - Blondie, Snuffy Smith, Dilbert, Pearls Before Swine, Zits, Pickles.
Then there are the ones I hate - foremost is Close to Home. I absolutely hate the artwork, the jokes are stupid most of the time, and it doesn't hold a candle to The Far Side (which it replaced in my paper, at least). And I also hate those drama comics like Mark Trail and The Phantom.