The best sitcom for me at the moment is Modern Family. I laugh so hard watching that show at times it feels like I'm going to pass out.
Sadly I actually like Two and a Half Men. Now that Charlie Sheen has been fired I probably won't watch it anymore. When a main character leaves a show, in most cases, it's never any good anymore.
I also like The Big Bang Theory. Being a bit of a nerd myself I can relate to those characters. Except Sheldon, he needs to be on meds for his OCD.
Family Guy, South Park and the Simpson's are my favorite cartoons. As a child however it was The Flintstones, The Jetsons and Scooby Doo that I liked to watch.
My favorite sitcoms from the past are I Love Lucy and The Golden Girls. I do love Lucy and even today nearly sixty years later, laugh to no end when I watch it. The same for The Golden Girls. Betty White's character "Rose", is my favorite. Sadly she is the only Golden Girl still living.
As far as Sketch shows Saturday Night Live is still my favorite. The Carol Brunette Show was also a good one.