How easy is this? How I Met Your Mother, of course. Well I tend to like all sitcoms no matter how cheesy it is, mainly because its easily digestable. But How I Met Your Mother is just a stand out sitcom that doesn't re-use jokes over and over and is unique in its set up.
Also, while most sitcoms attempt to use one liners to pass as a joke, HIMYM uses those one liners on purpose and clearly shows that they suck, hence it is funny.
But I also like other shows such as Scrubs, Two and a Half Men, Simpsons, Family Guy, Rove (before they quit), Futurama, Myth Busters, Top Gear, Big Bang Theory, Friends, Cougar Town, Naturally Sadie, The Latest Buzz, Bluewater High, Dilbert, Hannah Montana.
Just from the top of my head.